dissenting.
More than seventy years ago this Court upheld the regulation of grain warehousing rates by Illinois and did so despite the relation of the great grain elevators to interstate commerce. Munn v. Illinois, 94 U. S. 113; and see Budd v. New York, 143 U. S. 517. State regulation of grain elevators had become so much part of our economic and political fabric, and so important was it deemed that the State laws remain in full force, that when Congress, in 1916, passed the first Warehouse Act (Part C of the Act of August 11, 1916, 39 Stat. 446, 486), it made that Act subordinate to the requirements of State laws. The Court now holds that by the 1931 Amendment to that Act, 46 Stat. 1463, Congress not only made the federal legislation independent of State law to the full scope of federal regulation, but also nullified the extensive network of State laws regulating warehouses, even though such laws, in their actual operation, in nowise conflict with the operation of the federal law. The Court thereby uproots a vast body of State enactments which in themselves do not collide with the licensing powers of the Secretary of Agriculture. It does so on the ground that Congress, by the 1931 Amendment, provided that “the power, jurisdiction, and authority conferred upon the Secretary of Agriculture' under this Act shall be exclusive with respect to all persons securing a license hereunder so long as said license remains in effect.”
*239The decision of the case turns on the “power, jurisdiction, and authority” that Congress has deposited with the Secretary of Agriculture to the exclusion of action by a State. I could understand, though that is not my view, a holding that once a warehouseman chooses to obtain a federal license, he is quit of amenability to State law relating to the business of warehousing as such. On the other hand, the Amendment of 1931 may be read, without violence to its language, as designed not to displace all State regulation of warehousing, but merely to prevent conflict or even concurrence as to the very matters with which the Secretary of Agriculture can deal. This would leave State law to operate where it could without impinging on the limited regulatory functions assumed by the Federal Government. Such is my view. The Court’s conclusion is a kind of admixture of these two views. Today’s decision, apparently, does not altogether free federally licensed warehouses from State warehouse regulation, nor yet subject them to State laws, even though these State laws may harmoniously function without impinging on the licensing powers of the Secretary. To my way of thinking, the justification for conceding an undefined area to the States equally justifies leaving to the States all that is not irreconcilable with the full exercise of the licensing authority given to the Secretary of Agriculture.
The facts of the case are not in dispute. Rice, an owner and shipper of grain, filed with the Illinois Commerce Commission a complaint charging respondent warehouse owners with violations of the Illinois Public Utility Act (Ill. Rev. Stats. 1945, c. 111-2/3), the Illinois Grain Warehouse Act (Ill. Rev. Stats. 1945, c. 114 §§ 293-326 (a)), and Art. XIII of the Illinois Constitution. The violations charged include operation without a State license, exaction of unreasonable rates, failure to publish rates, failure to provide appropriate facilities, improper *240mixing of grades, discrimination in rates, and conflict of interests as grain-dealer and warehouseman. The respondents moved to dismiss the complaint on the ground that federal license placed them under the exclusive jurisdiction of the United States Warehouse Act, and the State’s authority was entirely superseded. Upon denial of this motion by the Illinois Commerce Commission, respondents applied to the United States District Court for an injunction against further State proceedings. What is before us is the ruling of the Circuit Court of Appeals that the District Court had erred in not granting the injunction.
This Court now orders the proceedings before the Illinois Commerce Commission to be enjoined, without knowledge on our part what it is that Illinois would exact of respondents. It has not yet been decided by the authoritative voice of Illinois law, the Supreme Court of Illinois, which of her regulatory requirements would survive respect by that Court for the controlling federal Act. This Court has heretofore acted on the wise rule that it will not “assume in advance that a State will so construe its law as to bring it into conflict with the federal Constitution or an act of Congress.” Allen-Bradley Local v. Board, 315 U. S. 740, 746. The suit in the District Court was, in any event, premature. It should, on familiar principles, be ordered held in the District Court until the claim of Illinois may be authoritatively ascertained in the State courts, thereby perhaps avoiding a claim of conflict between State and federal legislation. Compare the series of cases from Thompson v. Magnolia Petroleum Co., 309 U. S. 478, to Spector Motor Co. v. McLaughlin, 323 U. S. 101.
On the merits of the controversy our problem is to determine what freedom to regulate its grain warehouses has been left to Illinois, after Congress exercised its constitu*241tional power over such warehouses by adopting a licensing system to be administered by the Secretary of Agriculture under closely defined authority. Underlying the problem is the important fact that we are concerned with an economic enterprise which, while it has important radiations beyond State bounds, does not thereby lose special relations to the State in which it is conducted. And so we have once more the duty of judicially adjusting the'interests of both the Nation and the State, where Congress has not clearly asserted its power of preemption so as to leave no doubt that the separate interests of the States are left wholly to national protection.
The general considerations to be taken into account in striking a balance, and not to be acknowledged merely pla-tonically, have been indicated in my opinion in Bethlehem, Steel Co. v. New York State Labor Relations Board, 330 U. S. 767. Suffice it to say that due regard for our federalism, in its practical operation, favors survival of the reserved authority of a State over matters that are the intimate concern of the State unless Congress has clearly swept the boards of all State authority, or the State’s claim is in unmistakable conflict with what Congress has ordered.
Assuming that the undefined scope of Illinois law covers all the relief sought before the Illinois Commission, it is not suggested that there is actual conflict between the limited federal control through the licensing device and the policy of Illinois. Indeed, it seems to be admitted that the enforcement of the State Act might well effectuate, at least in some aspects, the policy of the federal statute. Moreover, despite a statement in the House Report that the purpose of the 1931 Amendment was to make the Act “independent of any State legislation on the subject” (H. Rep. No. 2314, 70th Cong., 2d Sess., p. 4), the Court does not find that in making “the power, *242jurisdiction, and authority conferred upon the Secretary of Agriculture . . . exclusive with respect to all persons securing a license” Congress insulated such licensed ware-housemen from further regulation by a State. What the Court holds is that if Congress has touched a subject matter it becomes untouchable by the State, though there is neither paper nor operating conflict between federal and State spheres of authority. Thus, while Congress has not given to the Secretary of Agriculture rate-fixing power, Congress, it is said, has inferentially deprived Illinois of the power she has exercised for seventy years to fix grain warehouse rates.
I cannot agree. As to rates, for example, Congress has merely given the Secretary power to revoke a license if its holder charges “unreasonable or exorbitant” rates. The practical assumption, I submit, is not that Congress has put an end to the tried machinery for rate-fixing by the States without putting another in its place. It is rather that it would permit its licensing authority to avail itself of the facilities of the established rate-fixing agencies of the States and cooperate with them in ascertaining whether Illinois licensees are charging “unreasonable and exorbitant” rates. Such would be the practicalities of government where both State and Nation have converging yet separate interests, and such authorized collaboration between national and State governments should be the assumption in construing the Act unless Congress has left no doubt that it was so bent on avoidance of all possible conflict that it left no room for concert. Indeed, the very section which confers “exclusive” authority upon the Secretary of Agriculture authorizes him “to cooperate with State officials charged with the enforcement of State laws relating to warehouses . . . .” 46 Stat. 1465.
By the United States Warehouse Act, Congress did not undertake a general, affirmative regulation of warehouses, *243even remotely comparable to its regulation of other public utilities. The Act was initiated as warehouse receipts legislation, written with the Uniform Warehouse Receipts Act in mind. Neither the language nor the history of the 1931 Amendment marks a departure from the basic design and policy of the legislation. Congress did not see fit to establish a compulsory, uniform, nation-wide system for the regulation of grain warehouses, essential links though they be in the chain of interstate commerce. Nor did Congress authorize the Secretary of Agriculture to formulate and enforce such a system. Even in its limited aspect, the Act does not apply to all warehouses affecting interstate commerce. Indeed, Congress exercised no compulsion over any warehouse. Congress merely offered to those who desired it the privilege of being a federal licensee. Anyone who wished might continue to operate as a warehouseman without a federal license. As to these there is no question but that State law controls. And even those who obtain a federal license cannot be compelled to perform any positive duties. Except for certain penalties for fraud, the only sanction for disobedience of the few duties imposed is loss of the license.
Congress was content to allow two warehousemen in similar circumstances to operate under different rules if one chose to seek a federal license and the other did not. It offered perquisites incident to such a license to a warehouseman who wanted them. Such a scheme does not persuasively indicate a purpose to free such a federal licensee from regulations to which others are subject and which are not in practical conflict with the requirements of the federal law. For instance, has Congress really expressed with reasonable clarity its purpose to forbid to the States the fixing of warehouse rates and thus deprive the States of a long-standing regulatory power which the United States chose not to assume? Is it not more con*244sistent with a proper regard for the interplay of State and national interests to assume that Congress was imposing a minimum of regulation for those who accepted federal licenses rather than to assume that by inferential sterilization of State laws Congress meant to make its optional and restricted requirements the maximum? The “power, jurisdiction, and authority” of the Secretary of Agriculture which after 1931 was to be “exclusive” are given full and fair scope if made to refer only to powers that the Secretary can effectively exercise. There is exclusion of State power as to what the Act, substantively speaking, includes, but not exclusion of a vast potential field of warehouse regulation, not within the active range of federal administration, simply because Congress dealt with a small part of it, and that only conditionally.
Nor is there anything in the history of the federal Act which requires such destructive consequences to a longstanding body of State enactments. When the 1916 Act was passed, Congress emphasized the need for State regulation by subordinating federal action to such regulation. By 1931 forty States had laws regulating warehouses, laws which at least in some aspect did not conflict with the powers vested in the Secretary of Agriculture. An impressively large number of States fixed warehouse rates. The Court now finds in the legislative history of the 1931 Amendment a purpose to wipe out all these regulations as to the holders of federal licenses.
That Amendment eliminated the subservience of the federal Act to the laws of the States, for such subservience really nullified the practical purposes at which Congress aimed in 1916 by a voluntary federal licensing system. The purpose was to make “the Federal act independent of State laws,” and to “place the Federal act on its own bottom.” While such language in a Committee Report, treated merely as words, might be interpreted as an im*245plicit, roughshod decimation of State authority over any aspect of warehousing which the federal licensing system touched, howsoever meagerly and indirectly, it is more consonant with a due regard for federal-State relations to find that the dominating object of the legislation controls what was meant by “independent of State laws.” For the dominant object was removal of those matters which were entrusted to the Secretary of Agriculture from subordination to State action. By saving the authority which it had given to the Secretary of Agriculture from being rendered futile by State laws, Congress ought not to be held to have nullified State laws whose continuing force would not hamper the Secretary of Agriculture in exercising the powers that Congress gave him. Evidence is lacking that Congress felt that the correction of the inadequacy which had revealed itself regarding the 1916 Act required withdrawal of federal license holders from the requirements of non-conflicting State regulation. So long as full scope can be given to the amendatory legislation without undermining non-conflicting State laws, nothing but the clearest expression should persuade us that the federal Act wiped out State fixation of rates and other State requirements deeply rooted in their laws. When neither the mischief at which the 1931 Amendment was directed, nor the policy, terms and structure of warehousing legislation by Congress in its entirety necessitate it, disregard of the delicate balance of Federal-State relations ought not to be attributed to Congress.
If so fundamental a change were designed, it would normally be reflected in the financial provisions made by Congress, and in the reports on the administration of the Act. The appropriations for administering the United States Warehouse Act show no substantial increase as a consequence of the 1931 Amendment. For the years pre*246ceding and those immediately following the Amendment, the appropriations were:
1929 (45 Stat. 539, 563). $240, 320
1930 (45 Stat. 1189, 1214). 256, 000
1931 (46 Stat. 392, 419). 241, 000
1932 (46 Stat. 1242, 1270). 312, 200
1933 (47 Stat. 609, 638). 313, 020
1934 (47 Stat. 1432, 1460). 296, 220
1935 (48 Stat. 467, 494). 271, 383*
Moreover, those charged with the enforcement of the Act seem to have been unmindful of the far-reaching consequences now imputed to it. The reports of the Secretary of Agriculture, of the Chief of the Bureau of Agricultural Economics, and of the Chief of Agricultural Marketing Service, for the years after 1931, disclose administrative attitudes and practices no different from those of preceding years. No mention is made of the State laws which, the Court now holds, were superseded though not conflicting with federal administration. In citing the advantages incident to a federal license, no mention appears of so important an item as relief from existing State regulations.
The history of the federal act shows that at no time has Congress deemed it desirable to introduce compulsory uniformity of warehouse regulation. By freeing federal licensees from overriding State regulation Congress was not by indirection seeking to create such a uniform system. But the effect of the interpretation now given to the 1931 Amendment is the establishment of uniformity of non-regulation, in that it introduces laissez jaire outside the very narrow scope of the Secretary’s powers. It is easy to exaggerate the danger of undesirable consequences flowing *247from a rejected construction. But surely one does not draw on idle fears in suggesting that as a result of today’s decision the gates of escape from deeply rooted State requirements will be open, although Congress itself has not authorized federal authority to take over the regulation of such activities and though their State enforcement does not at all conflict with, but rather promotes, the limited oversight of warehouses thus far assumed by the Federal Government. The Court displaces settled and fruitful State authority though it cannot replace it with federal authority.
The more substantial increases in appropriation after 1935 seem to be due to an increase in the volume of licensing, not to an extension of the fields of supervision.