delivered the opinion of the court.
The appeal involyes a consideration of the validity of the act of Congress of October 1, 1888, prohibiting Chinese laborers from entering the United States who had departed before its passage, having a certificate issued’ under the act of 1882 as' amended by the act of 1884, granting them permission to return. The validity of the act is assailed as being in effect. an - expulsion from the' country of Chinese' laborers, in violation of existing treaties between the United States and the government of China, and of rights vested in them under the laws of Congress.
It will serve to present with greater, clearness the .nature and force of the objections to the act, if a brief -statement be made of the general character of the treaties between the two' countries and of the legislation of Congress to carry them into execution.
*590The first treaty between the UnitechStates and the Empire of China was concluded on the 3d of July, 1844, and ratified in December of the following year. 8 Stat. 592. Previous to that time there had been an extensive commerce between the two nations, that to China being confined to a single port. It was not, however, attended by any serious disturbances between our people there and the Chinese. In August, .1842, as the result of a war between England and China, a treaty was concluded stipulating for peace and friendship between them, and, among other things, that British subjects, with thpir. families and establishments, should be allowed to reside for the pulpóse of carrying on mercantile pursuits at the five principal ports of the empire. 6 Hertslet’s Commercial Treaties, 221; 3 Nouveau Kecueil Général de Traités (1842), 484. Actuated by a desire to establish by treaty friendly relations between the United States and the Chinese Empire, and to secure to our people the same commercial privileges which had been thus conceded to British. subjects, Congress placed at the disposal of the President the means to enable him to establish future commercial relations between the two countries “ on terms of national equal reciprocity.” Act of March, 1843Vc. 90, 5 Stat. 624. \A mission was accordingly sent by him to China, at the head of which-was.placed Mr. Caleb Cushing, a gentleman of large experience in public affairs. He found the Chinese government ready to concede by treaty to the United States all that had- been reluctantly, yielded to England through compulsion. As the result of his negotiations the treaty of 1844 was concluded- It stipulated, among other things, that there should be a. “perfect, permanent and universal peace, and a sincere and cordial amity ” between the two nations; that the five principal ports of the empire should be opened' to the citizens-of-the United States, who should be permitted to reside with their families and trade there, and to proceed with their vessels and merchandise to and from any foreign port and either of said five ports; and while peaceably attending to their affairs should receive the protection of the Chinese authorities. Senate Document No. 138, 28th Cong.' 2d Sess.
*591The treaty between England and China did not have the effect of securing permanent peace and friendship between those countries. British subjects in China were often subjected not only to the violence of mobs, but to insults and outrages from local authorities of the country, which led to. retaliatory measures for the punishment of the aggressors. To such an extent were these measures carried,- ,and such resistance offered to them, that in 1856 the two countries were in open war. England then, determined, with the cooperation of France, between which countries there seemed to be perfect accord, to secure from the government of ‘China, among other things, a recognition of the right of other powers to be represented there by accredited ministers, an extension of commercial intercourse with that country, and stipulations fpr religious freedom to all foreigners there, and for the suppression of piracy. England requested of -the President the concurrence and active co-operation of the United States similar to that which France had accorded, and to authorize our naval and political authorities to act in concert with the allied forces. ■ As this proposition involved a participation in existing hostilities, the request could not be acceded to, and the Secretary of State in his communication to the English government explained, that the war-making power of the United States was not vested in the President but in Congress, and that he had no authority, therefore, to order aggressive hostilities to be undertaken; But as the rights of citizens of the United States might be seriously' affected by the results of existing hostilities, and commercial intercourse between the United States and China be disturbed, it was deemed advisable to. send to China a minister plenipotentiary to represent our government and watch our interests there. Accordingly, Mr. William B. Keed, of. Philadelphia, was appointed such minister, and instructed, whilst abstaining from any direct interference, to aid by peaceful cooperation the objects the allied forces were seeking to accomplish. Senate Document No. 47, 35th Cong. 1st Sess. Through him a new treaty was negotiated with the Chinese government. It was concluded in June, 1858, and ratified in. August of the following year. *59212 Stat. 1023. It reiterated'the pledges of peace and friendship between the two nations, renewed the promise of protection to all citizens of the United States in China peaceably-attending to their affairs, and stipulated for security- to Christlan§¡ in the profession of their religion. Neither the treaty of 1844, nor that .of 1858, touched upon the migration and emigration of the citizens and subjects of the two'nations respectively from one country to the other. But in 1868 a great change in the relations-of the two nations was made in that respect. In that year a-mission from China, composed.of dis-' tinguished functionaries ■ pf that empire, came tq the United States witjh. the professed object of establishing closer relations between the two countries and their peoples. At its head Was placed Mr. Anson Burlingame,, an eminent citizen of-the United States, who had at one time represented this country as commissioner to China. He resigned : his office under our government to accept the position tendered to him by the Chinese government. ’ The mission was hailed in -the United States as the harbinger of a new era in the history of China. — as the opening up to . free intercourse with 'other, nations and peoples a country that for ages had been isolated and closed against foreigners, who were allowed to have intercourse and to trade with the Chinese only at a few designated places; and the belief was general, and confidently expressed, that great benefits would follow, to the world generally and especially to the United States! On' its arrival in Washington, additional articles to the treaty of 1858 were agreed-upon, which gave expression to the general desire that the two nations and • their peoples should be drawn closer .together. The new articles, eight in number,, were agreed to on- the 28th of . July, 1868, and ratifications of them .were exchanged at Pekin in November of the following year. 16 Stat. .739. Of these articles the 5th, 6th 'and 7th are as follows: •
• “ Article V. The United States of America anfl the Emperqr of China cordially recognize the inherent and inalienable right of inaij. ‘to change his home and allegiance, and also the mutual.i advantage of the free migration and emigration of their citizens and subjects respectively from the One country *593to the other for purposes of curiosity, of trade, or as permanent residents. The high contracting parties, therefore, join in reprobating any other than an entirely voluntary emigration for these purposes. They consequently agree to pass laws making it a penal offence for a citizen of the United States or Chinese subjects to take Chinese subjects either to the United States or to any other foreign' country, or for a Chinese- subject or citizen of the United States to take citizens of the United States to China or to any other foreign country without their free and voluntary consent, respectively.
“Article YI. Citizens of the United States visiting or residing in China shall enjoy the same privileges, immunities or éxemptions in respect to travel or residence, as may there be enjoyed by the citizens or subjects of the most favored nation. And, reciprocally, Chinese subjects visiting or residing in the United States shall enjoy the same privileges, immunities and exemptions ’ in respect to travel or residence as may there be enjoyed by the citizens or subjects of the most favored nation. But nothing herein contained shall be' held to confer naturalization upon citizens of the United States in China, nor upon the subjects of China in the United States.
“Article YII. Citizens of the United States shall enjoy all the privileges of the public educational' institutions under the control of the government of China; and, reciprocally, Chinese subjects shall enjoy all the privileges of the public educational institutions under the control of the government of the United States, which • are enjoyed in the respective countries by the' citizens or subjects of the most favored nation. The citizens of the United States may freely establish and maintain schools within the Empire of China at those places where foreigners are by treaty permitted to reside; and, reciprocally, Chinese subjécts may enjoy the same privileges and immunities in the United States.”
But notwithstanding these strong expressions of friendship and good will, and the desire they evince for free intercourse, events were transpiring oh the Pacific Coast which soon dissipated the anticipations indulged as to the benefits to follow the immigration of Chinese to this country. The previous *594treaties of 1844 and 1858 were confined principally to mutual declarations of peace and friendship and to stipulations for commercial intercourse at certain ports in China and for protection to our citizens whilst peaceably attending to their affairs. It was not until the additional articles of. 1868 were adopted that any public declaration was made by the two nations that there were-advantages in the free migration and emigration of their citizens and subjects respectively from one country to the other; and stipulations given that each should enjoy in the country of the other, with respect to travel or residence, the “ privileges, immunities, and exemptions ” enjoyed - Tty- citizens or subjects of the most favored nation. Whatever modifications have since been made to these general provisions have been caused by a well-founded apprehension — from the experience of years — that a limitation to the immigration of certain classes from China was essential to the peace of the community on the Pacific Coast, and possibly to the preservation of our civilization there. A few words on this point may not be deenied inappropriate here, they being confined to matters of public notoriety,- which have frequently been brought to the. attention of Congress. Report of Committee.of H. R. No, 872, 46th. Cong. 2d Sess.
The discovery of gold in California in 1848, as is well known, was followed by a large immigration thither from all parts of the world, attracted not only by the hope of gain from the mines, but from the great prices paid for all kinds of labor. The news of the discovery penetrated China, and laborers came from there in great numbers, a few with' their own means, but by far the greater number under contract with employers, for whose benefit they worked. These laborers readily secured employment, and, as domestic servants, and in various kinds of out-door work, proved to be exceedingly useful. For some years little opposition was made to them except when they sought to work in the mines, but, as their numbers increased, they began to engage in various mechanical pursuits and trades, and thus came iff competition with our artisans and mechanics, as well as our laborers in the field.
The competition steadily increased as the laborers came in *595crowds- on each steamer that arrived from China, or. Hong Kong, an adjacent English port. They were generally industrious and frugal. Not being accompanied by families, except in rare instances, their expenses were small; and they were content with the simplest fare, such as would not suffice for our laborers and artisans. The competition between them and our people was for this reason altogether in their favor, and the consequent irritation, proportionately deep and bitter, was followed, in many- cases, by open -conflicts, to' the great disturbance'of the public peace.
The differences of race added greatly to the difficulties of the situation. Notwithstanding the favorable provisions of. the'new articles of the treaty of 1868, by which all the privileges, immunities, and exemptions were extended to subjects of China in the United States which were accorded,to citizens or subjects of the most favored nation, they remained strangers in the land, residing apart by themselves, and adhering to the customs and usages of their own country. It seemed impossible for them to assimilate with our people or to make any change in their habits or modes of living. As they grew in numbers each year the people of the coast saw-, or believed they saw, in the facility of immigration, and in the crowded millions of China, where population presses upon the means of subsistence, great danger that at no distant day that portion of our country would be overrun by them unless prompt action Was taken to restrict their immigration. The people there accordingly petitioned earnestly for protective legislation.
In December, 1878, the convention which framed the present constitution of California, being , in session, took this subject up, and memorialized Congress upon it, setting forth, in substance, that the presence of Chinese laborers had a baneful effect upon the material interests of the State, and upon public, morals; that their immigration'was in numbers approaching the- character of an Oriental invasion, and was a menace to' our civilization; that .the discontent from this cause was not confined to any political party, or to any class or nationality, but was well-nigh universal; that they retained the habits and customs of their own country, and in fact constituted a *596Chinese settlement within the State, without; any interest in our country or its institutions; and praying Congress to. take measures to prevent their further immigration. , This memorial was presented to Congress in February, 1879.
So urgent and constant were the prayers for relief' against existing, and anticipated evils, both from the public authorities of the Pacific Coast and from private individuals, that Congress was- impelled to act on the subject. Many persons, however, both in and out of Congress, were of opinion that so long as the treaty remained unmodified, legislation restricting immigration would be a breach of faith with China. A statute was accordingly passed appropriating money to send commissioners to Chipa to act with our minister there in negotiating and concluding by treaty a settlement of such matters of interest between the two governments as might be confided to them. 21 Stat. 133, c. 88. Such commissioners were appointed, and as the result of their negotiations the supplementary treaty of November 17, 1880, was concluded and ratified in May of the following year. 22 Stat. 826.. It declares in its first article that “ Whenever, in the opinion of the Government of the United States, the coming of Chinese laborers to the United States, or their residence therein, affects or threatens to affect the interests- of that country, or to endanger the good order of the said country or of any locality within the territory thereof, the Government of China agrees that the Government of the United States may regulate, limit, or suspend such coming or residence, but may not absolutely prohibit it. The limitation or suspension shall ", be reasonable and shall apply only to Chinese who may go to the United States as laborers, other classes not being included ip the limitations. Legislation taken in regard to Chinese laborers will be of such a character only as is necessary to enforce, the regulation, limitation, or suspension of immigration, and immigrants shall not be subject to personal maltreatment or abuse.” In its second article' it' declares that “ Chinese subjects, whether proceeding to the United States as teachers, students, merchants, or from curiosity, together with their body and household servants, and Chinese laborers who are now in the United States shall *597be allowed to go and come of tbeir own free will and accord, and shall be accorded all the rights, privileges, immunities and exemptions which are accorded to the citizens and subjects of the most favored nation.”'
The government of China thus agreed that notwithstanding the stipulations of former treaties, the United States might regulate, limit, or suspend the coming of Chinese laborers, or their residence therein, without absolutely forbidding it, whenever in their opinion the interests of the. country, or of any part of it, might require such action. Legislation for such regulation, limitation, or suspension was entrusted to the discretion of our government, with the condition that it should only be such as might be necessary for that purpose, and that the immigrants should not be maltreated or abused. On the 6th of May, 1882,.an act of Congress was approved, to carry this supplementary treaty into effect. 22 Stat. 58, c. 126. It is entitled “ An act to execute certain treaty stipulations relating to Chinese.” Its first section declares that after ninety days from the .passage of .the act, and for the period of ten years from its date, the coming, of Chinese laborers to the United States is suspended, and that it shall be unlawful for any such laborer to come, or, having come, to remain within the United States. The second makes it a misdemeanor, punishable by fine, to which imprisonment may be added, for the master of any vessel knowingly to bring within. the United States from a foreign- country, and land, any such Chinese laborer. The third provides that those two sections shall not apply to Chinese laborers who were in the United. States November 17, 1880, or who should come within ninety days-after the passage of the act. The fourth declares that, for the purpose of identifying the laborers who were here 'on the 17th of November, 1880, or who should come within the ninety days mentioned, and to-furnish them with “the proper evidence” of their right to go from and come to the United States, the “ collector of customs of the district from which any such Chinese laborer shall depart from the United States shall, in person or by deputy, go-on* board each, vessel having on board any such Chinese laborer and cleared or about to sail *598from his district for a foreign port, and on suoh vessel make a. list of all such Chinese laborers, which shall be entered in reg-' istry books to be kept for that purpose, in which shall be stated the name, age, Occupation, last place of residence, physical marks or peculiarities and all facts necessary for the identification of each of suck Chinese laborers, which books shall be safely kept in the custom-house;’” and each laborer thus departing shall be entitled to receive, from the collector or his deputy, a certificate containing such particulars, corresponding with the registry, as may serve to identify him. The. certificate herein provided for,” says the section, “ shall entitle the Chinese laborer to whom the same is issued to return to and re-enter the United States upon producing and delivering th'e same to the collector of customs of the district at which such Chinese laborer shall se,ek to re-enter.”
The enforcement of this act with respect to laborers who were in the United States on November 17, 1880, was attended with great embarrassment, from the suspicious, nature, in many instances, of the testimony offered to establish the residence of the parties, arising from the loose notions entertained by the witnesses of the obligation of an oath. This fact led to a desire for further legislation restricting the evidence receivable, and the amendatory act of July 5, 1884, was accordingly passed. 23 Stat. 115, c. 220. The committee of the House of Representatives on foreign affairs, to whom the original bill was referred, in reporting it back, recommending its passage, stated that there had been such manifold evasions, as well as attempted evasions, of the act of 1882, that it had failed to meet the demands which called it into existence.Report in H. R. No. 614, 48th Cong. 1st -Sess. To obviate the difficulties attending its enforcement the amendatory act of 1884 declared that the certificate which the laborer must obtain “ shall be the only evidence permissible to establish his right of re-entry” into the..United States.
This act was held by this court not to require the certificate from laborers who were in the United States on- the 17th of November, 1880, who had departed out of the country before May 6, 1882, and remained out until after July 5, 1884. *599Chew Heong v. United States, 112 U. S. 536. The same difficulties and embarrassments continued with respect to the proof of their former residence. Parties were able to pass successfully the required examination as to their residence before November 17; 1880, who, it was generally believed, had never visited our shores. To prevent the possibility of the policy of excluding Chinese laborers being evaded, the act of October 1, 1888, the validity of which is the subject, of consideration in this case, was passed. It is entitled “An. acta supplement to an act entitled ‘ An act to execute certain treaty stipulations relating to Chinese,’ approved the sixth day,of May, eighteen hundred and eighty-two.” 25 Stat. 504, c. 1064: It is as follows:.
“ Be it enacted by the Senate and House of Bepresentatmes of the United States of America in Congress assembled,' That from and after the passage of this act, it shall be unlawful' for any Chinese laborer who shall at any time heretofore have been, or who may now. or hereafter be, a resident within the United States, and who shall have departed, or shall depart therefrom, and shall not have returned before the passage of this act, to return to, or remain in, the United States.
“ Sec. 2. That no certificates of identity provided for in the fourth and fifth sections of the act to which this is- a supplement shall hereafter be issued; and every certificate heretofore issued in pursuance thereof is-hereby declared void .and of no effect, and the Chinese laborer claiming admission by virtue thereof shall not be permitted to enter the United States.
“ Sec. 3. That all the duties prescribed, liabilities, penalties, and forfeitures imposed, and the powers -conferred bv the second, tenth, eleventh and twelfth sections of the act (to which this is a supplement,- are hereby extended and made applicable to the provisions of this act. '
“ Sec. 4. That all such part or parts -of the act to which' this is a supplement as are inconsistent herewith are hereby repealed.
“ Approved October 1, 1888.”
The validity of this act, as already mentioned, is assailed, as being in effect an expulsion from the country of Chinese *600laborers in violation of existing treaties between the United States and the government of China, and of rights vested in them under the laws of Congress. The objection that the act is in conflict with the treaties was earnestly pressed in the court below, and the answer to it constitutes the principal part of its opinion. 36 Fed. Kep. 431. Here the objection made is, that the act of 1888 impairs a right vested under the treaty of 1880, as a law of the United States, and the statutes of 1882 and of 1884 passed in execution of it. It must be conceded that the act of 1888 is in contravention of express stipulations of the treaty of 1868 and of the supplemental treaty of 1880, but it is not on that account invalid or to be restricted in its enforcement. The treaties were of no greater legal obligation than the act of Congress. By the Constitution, laws made in pursuance thereof and treaties made under the authority of the United States are both declared to be the supreme-law of the land, and no paramount authority is given to one over the other. A treaty, it is true, is in its nature a contract between nations and is often merely promissory in its character, requiring legislation to carry its stipulations into effect. Such legislation will be open to future repeal or amendment. If the treaty operates by its own force, and relates to a subject within the power of .Congress, it can be deemed in that particular only the equivalent of a legislative act, to be repealed or modified at the pleasure of Congress. In either case the last expression of the sovereign will must control.
The effect of legislation upon conflicting treaty stipulations was elaborately considered in The Head Money Cases, and it was there adjudged' “ that so far as a treaty made by the United States with any foreign nation can become the subject of judicial -cognizance in the courts of this country, it is subject to such acts as Congress may pass for its enforcement, modification, or repeal.” 112 U. S. 580, 599. This doctrine was affirmed and followed in Whitney v. Robertson, 124 U. S. 190, 195. It will not be presumed that the legislative department of the government will lightly pass laws which are in conflict with the treaties of the country; but that circumstances may arise which would not only justify the government in disre*601gárding their stipulations, but demand in the interests of the country that it should do so, there' can be no question. Unexpected events may call for a change in the policy of the country. Neglect or violation of stipulations. on the part, of the other contracting.party may require corresponding^ action on our part. When a reciprocal engagement is not carried out by one of the contracting -parties, the other may also decline to keep the corresponding engagement. In 1798 the conduct towards this country of the government of France was of such a character that Congress declared that the United States were freed and exonerated from the stipulations of previous treaties with that country.. Its act on the subject was as follows:
“An Act to declare the treaties heretofore concluded with France, no longer obligatory on the United States.
“ Whereas the treaties concluded between the United .States and France have been repeatedly violated on the part of the French government; and the just claims of the United States for reparation of the injuries so committed have been refused; and their attempts to negotiate an amicable adjustment of all-complaints between the two nations have been repelled with indignity; And whereas, under authority of the French government, there is yet pursued against the United States a. system of predatory violence,- infracting the said treaties, and hostile to the rights of a free and independent nation:
“ Be~it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That the United States are of right freed and exonerated from the stipulations of the treaties, and of. the consular convention, heretofore-concluded between the United States and Frapce; and that the same shall not henceforth be regarded as legally, •obligatory on the government or citizens of the United States.” 1 Stat. 578, c. 67.
This act, as seen, applied in terms only to the future. Of course, whatever of a permanent character had been executed or vested under the treaties was not affected by it. . In that respect the abrogation of the obligations of a treaty operates, *602like the repeal of a. law, only upon the future, leaving transactions executed under it to stand unaffected. The validity of this legislative release from the stipulations of the treaties was of course not a matter for judicial cognizance. The question whether our government is justified in disregarding its engagements with another nation is not one for the determination of the courts. ' This subject was fully considered by Mr. Justice Curtis, whilst sitting at the circuit, in Taylor v. Morton, 2 Curtis, 454, 459, and he held that whilst it would always be a matter of the utmost gravity and delicacy to refuse to execute a treaty, the power to do so was prerogative, of which no nation could be deprived without deeply affecting its independence ; but whether a treaty with a foreign sovereign had been violated by him, whether the consideration of a particular stipulation of a treaty had been voluntarily withdrawn by one party so as to no longer be obligatory upon the other, and whether the views, and acts of a foreign sovereign, manifested through his representative, had given just occasion to the political departments of our government to withhc d the execution of a promise contained in a treaty or to act in direct contravention of such promise, were not judicial, questions ; that the power to determine them has not been confided to' the judiciairy, which has no suitable means to execute it, but to the executive, and legislative departments of the government ; and that it belongs to diplomacy and legislation, and not to the administration of existing laws. And the learned justice, added,, as a necessary consequence of these conclusions, . that if Congress .has this power, it is wholly immaterial to inquire whether it has, by the statute complained of, departed from the treaty or not; or, if it has, whether- such departure was accidental or designed; -and if. the latter, whether the reasons therefor were good or bad. These views were reasserted and fully adopted by this court in Whitney v. Robertson, 124 U. S. 190, 195. And may add to the concluding observation of the learned justice, that if the power mentioned is vested in Congress, any reflection upon its motives, or the motives of any of its members- in exercising it, would be entirely uncalled for.- This court is not a censor of the morals *603of other departments of the government.; it is not invested with any authority to pass judgment upon the motives of their conduct. "When once it is established that Congress, possesses the power, to pass an act, our province ends with its construction, and its application to cases as they are presented- fiar determination. Congress has the power under the Constitution to declare war, and in two instances where the power has been exercised — in the war of 1812 against Great Britain, and in 1846 against Mexico — the propriety and-wisdom and justice of its action were vehemently assailed by some of the ablest and best men in the country, but no one doubted the legality of the proceeding, and any imputation by this or any other court of the United States upon the motives of the members of Congress who in either case voted for the declaration, would have been justly the cause of animadversion. We do not mean to intimate that the moral aspects of'legislative acts may hot be proper subjects of consideration. Undoubtedly they may be, at proper times and places, before, the public, in the halls of Congress, and in. all the modes by which the public mind can be influenced. Public opinion thus enlightened, brought to bear upon legislation, will do more than all other causes to prevent abuses; but the province of the courts is to pass upon the validity of laws, not to make them, and when their validity is established, to declare their meaning and apply their provisions. All else lies beyond their domain.
. There being nothing in the treaties between China and the United States to impair the validity, of the act of Congress of-October 1, 1888, was it on any other ground beyond the competency of Congress to pass it ? If so, it must be because it was not within the power of Congress to prohibit Chinese laborers who had at the time departed from the United States, or should subsequently depart, from returning to the United States.' Those laborers are not citizens of the United States; they are aliens. That the government of the United States, through the action of the legislative department, can exclude aliens "from its territory, is a proposition which we do not think open to controversy. Jurisdiction over its own territory to that extent is an incident of every independent nation.’ It is a part. of its in*604dependence. If it could not exclude aliens it would be to. that. extent subject to the control of another power. As said by this court in the. case of The Exchange, 7 Cranch, 116, 136, speaking by Chief Justice Marshall:. “The jurisdiction of the nation within its own territory is necessarily exclusive and absolute. It is susceptible of no limitation not imposed by itself. Any restriction upon it, deriving validity.from an external source, would imply a diminution of its sovereignty to the extent of the restriction, and an investment of that sovereignty to the same extent in that power which could impose such restriction.-. All exceptions, therefore, to the full and complete power of a nation within its own territories, must be'traced up to the consent of the nation itself. They can flow from no other legitimate source;”
While under our. Constitution and form of government the great mass of local matters is controlled by local authorities, the, United States; in their relation to foreign countries and their- subjects or citizens are one nation, invested with powers which belong to independent nations, the exercise of which can be invoked for the maintenance of its absolute independence and security throughout its entire territory. The powers to declare war, make treaties, suppress insurrection, repel invasion,, regulate foreign commerce, secure republican governments to the States, and admit subjects of other nations .to citizenship, are all sovereign powers, restricted in their exercise only by the Constitution itself and considerations of public policy and justice which control, more or less, the conduct of all civilized nations. As said by this court in the case of Cohens v. Virginia, 6 Wheat. 264, 413, speaking by the sainé great Chief Justice: “ That the United States'form, for many, and for most important purposes,-a single nation, has not yet been , denied, in war, .wé are . one people. In making peace /we are one people. In all commercial regulations, we are one land the same people. In many other respects, the American-people are one; and the government winch is alone capable* of controlling and managing their interests in all these respects, is the government of the Union. It is their government, and in that characterthey have no other. America has chosen to *605be in many respects, and to many purposes, a. nation; and for all these purposes her government is complete; to all these objects, it is competent. The people have declared, that in the exercise of all powers given for these objects, it is supreme. It can then in affecting these objects legitimately control all individuals or governments within the American territory. The constitution and laws of a State, so far as they are repugnant to the Constitution and laws of the United States, are absolutely void. These States are constituent parts of the United States.' They are members of one great empire — for some-.purposes sovereign, for some purposes subordinate.” The same view is expressed in a different form by Mr. Justice Bradley, in Knox v. Lee, 12 Wall. 457, 555, where he-observes that “the United States is not only a government, but it is a national government, and the only government in this country that has the character of nationality. It is invested with power over all the foreign relations of the country, war, peace and negotiations and intercourse with other nations; all. which are forbidden to the state governments. It has jurisdiction, over all those general subjects of legislation and sovereignty which affect the interests of the whole people equally and alike, and which require uniformity of regulations and laws, such as the coinage, weights and measures, bankruptcies, the postal system, patent and copyright laws, the public lands and interstate commerce, all which subjects are expressly or impliedly 'prohibited to the state governments. It has power to suppress insurrections, as well as to repel invasions, and to organize, arm, discipline and call into service the militia of the whole country; The President is charged with the. duty and invested with the power to take care that the laws be faithfully executed. The judiciary has jurisdiction to decide controversies between the States, and, between, their respective citizens, as well as questions of national concern; and the government is clothed with power to guarantee to every State a republican form of government, and to protect each of them against invasion and domestic violence.”
The control of local matters being left to local authorities, and national matters being entrusted to the government of the *606Union, the problem of free institutions existing over a widely extended country, having different climates and varied interests, has been happily solved'.' For local interests the several States of the Union exist, but for national purposes,, embracing our relations with foreign nations, we are but one people, one nation, one power.
To preserve its independence, and give security against foreign aggression and encroachment, is the highest duty of every nation, and to attain these ends nearly all other considerations are to be subordinated. It matters not in what form such aggression and encroachment come, whether from the foreign nation acting in its national character or from vast hordes, of its people crowding in upon us. ' The government, possessing the powers which are to be exercised for protection and security, is clothed with authority to determine the occasion on which the powers shall be called forth; and its determination, so far as the subjects affected are concerned, are necessarily conclusive upon all its departments and officers. If, therefore, the government of the United States, through its legislative department, considers the presence of foreigners of a different race in this country, who will not assimilate with us, to be dangerous to its peace and security, their exclusion is not to be stayed because at the time there are no actual hostilities with- the nation of which the foreigners are subjects. The existence of war would render the necessity of the proceeding only more obvious and pressing. The same necessity, in a less pressing degree, may arise when war does, not exist, and the same authority which adjudges the necessity in one case must also” determine it in the other. In both cases its determination is conclusive upon the judiciary. If the government of the country of which the foreigners .excluded are subjects is dissatisfied with this action it can make complaint to the executive head of our government, or resort to any other measure which, in its-judgment, its interests or dignity may demand; and there lies its only remedy.
The'power of the government to exclude foreigners from the country whenever, in. its judgment, the public interests require such exclusion, has been asserted in repeated instances, *607and never denied by the executive or legislative departments. In a communication made in December, 1852, to M^. A. Dudley Mann, at one time a special agent of the Department of State in Europe, Mr. Everett, then Secretary of State under President Eillmore, writes: “ This government could never give up the right of excluding foreigners whose presence it might deem a source of danger to the United States.” “ Nor will this government consider such exclusion of American citizens from Bussia necessarily a matter of- diplomatic complaint to' that country.” In a dispatch to Mr. Fay, our minister to Switzerland, in March, 1856, Mr. Marcy, Secretary of State under President Pierce, writes: “Every society possesses the undoubted right to determine who shall compose its members, - and it is exercised by all nations, both in peace and war.” “ It may always be questionable whether a resort to this power is warranted by the circumstances, or what department of the government is empowered to -exert it; but there can be no doubt that it is possessed by all nations, and that each may decide for itself when the occasion arises demanding its exercise.” In a communication in September, 1869, to Mr. Washburné, our minister to France, Mr. Fish, Secretary of State under President Grant, uses this language: “ The control of the people within its limits, and the right to expel from its territory persons who are dangerous to the peace of the State, are too clearly within the essential attributes of sovereignty to be seriously contested. Strangers visiting or sojourning in a foreign country voluntarily submit themselves to its laws and customs, and the municipal laws of France, authorizing the expulsion of strangers, are not of such recent date, nor has the exercise of the power by the government of France been so infrequent, that sojourners within her territory can claim surprise when the power is put in force.” In a communication to Mr. Foster, our minister to Mexico, in July, 1819, Mr. Evarts, Secretary of State under President Hayes, referring to the power vested in the constitution of Mexico to expel objectionable foreigners, says: “ The admission that, as that constitution now stands and is interpreted, foreigners who render themselves harmful or objectionable to the general govern*608ment must expect to be liable to the exercise of the power adverted Ijo, even in time of peace, remains, and no good reason is. seen for departing from that conclusion now. But, while there may be no expedient basis on which to found objection, on principle and in advance of a special case thereunder, to the' constitutional right thus asserted by Mexico, yet the manner of carrying out such asserted right may be' highly objectionable. You would be fully justified in making earnest remonstrances should a citizen of the United States be expelled' from Mexican territory without just steps to assure the grounds of such expulsion, and in bringing the fact to the immediate knowledge of the Department.” In a communication to Mr. W. J: Stillman, under date of August'3, 1882,. Mr. Frelinghuysen, Secretary • of State under President Arthur, writes •: “ This government cannot contest the right of foreign governments to exclude, on police or other grounds, American citizens' from their shores.” "Wharton’s International' Law Digest,. § 206. ' .
The exclusion of -paupers, criminals-and persons afflicted with incurable diseases, for which statutes have been passed, is only an application of the same power to particular classes of persons, whose'presence is deemed injurious or q source of danger -to the country. As applied to them; there) has never been any question as to the power to exclude them. The power is constantly exercised; its existence is involved in the right of self-preservation. -As to paupers, itT makes no difference by whose aid they are brought to the country. As Mr. Fish, when Secretary, of v State, wrote, in a communication under date of December 26, 1812, to Mr. James Moulding, of Liverpool, the government of the United States “is' not willing and will not consent to receive the pauper class of any. community who may. be sent or may be assisted in their immigration at the expense of government or of municipal authorities.”- As to criminals, the power of exclusion has always been exercised, even in the absence of any statute on the subject. In a despatch to Mr. Cramer, our minister to Switzerland, in December, 1881, Mr. Blaine, Secretary of State under President Arthur,- writes: “While, under the Constitution and *609the laws, this country is open to the honest and industrious immigrant, it has no room outside-of its prisons or almshouses for depraved and incorrigible criminals or hopelessly dependent paupers who may have become a pest or burden, or both, to their own country.” Wharton’s Int. Law Dig., supra.
The power of exclusion of foreigners being an incident of sovereignty belonging to the government of the United States, as a part of those sovereign powers delegated by the Constitution, the right to its exercise at any time when, in the judgment of the government, the interests of the country require it, cannot be granted away or restrained on behalf Of any one. The powers of government are delegated in trust to the United States, and are incapable of transfer to any other parties. They cannot be abandoned or surrendered. Nor can their exercise be hampered, when needed for the public good, by any considerations of private interest.' The exercise of these public trusts is not the subject of barter or contract. Whatever license, therefore, Chinese laborers, may have obtained, previous to the áct of October 1, 1888, to return to the United States áfter their departure, is held at the will of the government, revocable -at any time, at its pleasure. Whether a proper consideration by our government of its previous laws, or a proper respect for the nation whose subjects are affected by its action, ought to have qualified its, inhibition and made it applicable only to persons departing from the country after the passage of the act, are not questions for judicial determination. If there be any just ground of complaint on the' part of China, it must be made to the political department of our government, which is alone competent to act upon the subject. The rights and interests created by a treaty, which hfyve become so vested that its expiration or abrogation will fipt destroy or impair them, are such as are connected- with -and lie in property, capable of sale and transfer, or other disposition, not such as are personal and untransferable in their char-: acter. Thus'in, The Head Money Cases, the court speaks of certain rights being in some instances conferred upon the citizens or subjects of one nation residing in the territorial limits of the other, .which are “capable of enforcement as *610between private parties in the courts of the country.” “ An illustration of this character,” it adds, “ is found in treaties which regulate the mutual fights of citizens and subjects of the contracting nations in regard to rights of property by descent or inheritance, when, the individuals concerned are aliens.” 112 U. S. 580, 598. The passage cited by counsel from the language of Mr. Justice Washington in Society for the Propagation of the Gospel v. New Haven, 8 Wheat. 464, 493, also illustrates this doctrine. There the learned justice observes that “ if real estate be purchased or' secured under a treaty, it would be most mischievous to admit that the extinguishment of the treaty extinguished the right to such estate. In truth, it no more affects such han the repeal of a municipal law affects rights acquired under it.” Of this doctrine there can be no question in this court; but far different is this case, where a continued suspension of the exercise of a governmental power is insisted upon as a right, because, by the favor and consent of the government, it has not heretofore been exerted with respect to the appellant or to the class to which he belongs.’ Between, property rights not affected by the termination or abrogation of a treaty, and expectations of benefits from the continuance of existing legislation, there is as wide a difference- as between realization and hopes.
During the argument reference was made by counsel to the alien law of June 25, 1798, and to- opinions expressed at the time by men of great ability and learning against its constitutionality. 1 Stat. 570, c. 58. We do not attach importance-to those .opinions in their bearing upon this case. The act vested in the President power to order all such aliens as he should judge dangerous to the peace and safety of the United States, or'should have reasonable grounds to suspect were concerned in -any treasonable or secret machination against the government,, to depart out of the territory of the United States within such time as should be expressed in his order. There were other'provisions also distinguishing it. from the act under -consideration. The act was passed during a period of great political excitement, and it was attacked and .defended with great *611zeal and ability. It. is enough, however, to say that it is entirely different from the- act before us, and the validity of its provisions was never brought to the test of judicial decision in the courts of the United States.
Order affirmed.