with whom Mr. Justice Rehnquist joins, dissenting.
We are asked in this case to decide whether federal law prohibits the State of California from treating as community property a divorcing husband’s expectancy interest in pension benefits afforded under the Railroad Retirement Act of 1974. There can be no doubt that the State is free to treat this interest as property. Herb v. Pitcairn, 324 U. S. 117, 125-126. The only question, therefore, is whether something in the federal Act prevents the State from applying its normal substantive property law, under which assets acquired during marriage are commonly owned by the husband and wife. From the Court’s own review of the Railroad Retirement Act, it is apparent to me that the asserted federal conflict with California community property law — far from being grounded upon the concrete expressions that ordinarily are required to support a finding of federal pre-emption, see, e. g., Wissner v. Wissner, 338 U. S. 655 — is patched together from statutory provisions that have no relationship at all to substantive marital property rights. Indeed, the federal “policies” the Court perceives amount to little more than the commonplace that retirement benefits are designed to provide an income on retirement to the employee. There is simply nothing in the Act to suggest that Congress meant to insulate these pension benefits from the rules of ownership that in California are a normal incident of marriage.
I
Congress, when it acts, ordinarily does so “against the background of the total corpus juris of the states.” Wallis v. Pan American Petroleum Corp., 384 U. S. 63, 68 (citation *592omitted). In any case where it is claimed that a federal statute pre-empts state substantive law, therefore, it is essential to understand what the state law is. Perez v. Campbell, 402 U. S. 637, 644; Merrill Lynch, Pierce, Fenner & Smith, Inc. v. Ware, 414 U. S. 117. Although the question here arises in the context of a proceeding to dissolve a marriage, the state law at issue has to do with the ownership of property during marriage. Despite the Court’s repeated suggestions to the contrary, community property law is simply not a body of law that is designed to provide a “benefit” for a divorced spouse.
“Community of property between husband and wife is that system whereby the property which the husband and wife have is common property, that is, it belongs to both by halves.” W. deFuniak & M. Vaughn, Principles of Community Property § 1, p. 1 (2d ed. 1971) (hereinafter Principles). This definition of the property rights of a married couple was first recognized in written form in 693 A. D. in Visigothic Spain, id., § 2, p. 3, and now prevails in eight States of the Union. As we have recognized many times in the past, the community property system reflects a concept of property and of the marital relationship entirely different from that at common law. See Poe v. Seaborn, 282 U. S. 101; Bender v. Pfaff, 282 U. S. 127; Hopkins v. Bacon, 282 U. S. 122; United States v. Yazell, 382 U. S. 341., See generally Principles. Fundamental to the system is the premise that husband and wife are equal partners in marriage. Id., §2, p. 5; W. Reppy & W. deFuniak, Community Property in the United States 13 (1975). Each is deemed to make equal contributions to the marital enterprise, and each accordingly shares equally in its assets. Principles § 11.1, p. 28.
Under the Spanish ganancial system followed in our community property States, property acquired before the marriage or after its termination is the separate property of the spouse who acquired it. Id., § 1, p. 1; Prager, The Persistence of Separate Property Concepts in California’s Community Prop*593erty System, 1849-1975, 24 UCLA L. Rev. 1, 6 (1976). All property acquired during the marriage, however, is presumed to be community property. See, e. g., Meyer v. Kinzer, 12 Cal. 247, 251-252. The presumption is regarded as a rulé of substantive property law, not one of procedure or evidence. Nilson v. Sarment, 153 Cal. 524, 96 P. 315. Cf. Poe v. Seaborn, supra. In general, all property which stems from the labors of either spouse during the marriage, “irrespective of direct contributions to its acquisition or the condition of title” is, in the absence of an agreement between the spouses to the contrary, community property. Prager, supra, at 6. The spouses are deemed to have contributed equally to the acquisition of the property, regardless of the actual division of labor in the marriage and regardless of whether only one spouse formally “earned” it. Ibid.1
The interests of the spouses in the assets of the marital community are “during continuance of the marriage relation . . . present, existing and equal interests.” Cal. Civ. Code Ann. § 5105 (West Supp. 1978). Upon dissolution of the marriage, each possesses an equal and absolute right to his or her one-half interest. Meyer v. Kinzer, supra, at 251-252; In re Marriage of Brown, 15 Cal. 3d 838, 848, 544 P. 2d 561, 567. The right of each spouse to his or her share of the community assets, then, is a substantive property right entirely distinct from the right that a spouse might have to the award of alimony upon dissolution of the marriage. A community property settlement merely distributes to the spouses property which, by virtue of the marital relationship, he or she already owns. An alimony award, by contrast, reflects a *594judgment that one spouse — even after the termination of the marriage — is entitled to continuing support by the other.
In California, retirement benefits attributable to employment during marriage are community property. In re Marriage of Brown, supra. As long as the employee spouse has some reasonable expectancy of receiving the benefits in the future, the nonemployee spouse’s interest may attach even if the pension rights are not formally “vested.” Ibid. Pension rights created by act of the state legislature have been treated as community property by the California courts, Cheney v. City and County of San Francisco, 7 Cal. 2d 565, 61 P. 2d 754, as have federal military pension benefits, In re Marriage of Fithian, 10 Cal. 3d 592, 517 P. 2d 449, and benefits afforded by the federal civil service retirement plan, In re Marriage of Peterson, 41 Cal. App. 3d 642, 115 Cal. Rptr. 184. The California Supreme Court in this case, having found no conflict with the express provisions or policies of the Railroad Retirement Act, applied these settled rules of state marital property law to the petitioner’s expectation of receiving the retirement benefits afforded by the Act. The State’s decision to treat as property benefits that arguably are not “vested” is one that it is free to make. The only question for this Court, then, is whether the State can, consistently with the federal Act, follow its normal substantive community property law in dealing with these prospective benefits.
II
It is clear that Congress, when it established the railroad retirement system, did not purport to regulate the marital property rights of workers covered by the Act. Federal preemption, then, must be based on a perceived conflict between the provisions of the Act and the substantive law of California. Merrill Lynch, Pierce, Fenner & Smith, Inc. v. Ware, supra, at 127; New York Dept. of Social Services v. Dublino, 413 U. S. 405, 423 n. 29. When the state substantive law in *595question regulates family and family-property arrangements— matters that traditionally have been left to local law, see In re Burrus, 136 U. S. 586, 588-594; De Sylva v. Ballentine, 351 U. S. 570, 580 — state interests “should be overridden by the federal courts only where clear and substantial interests of the National Government, which cannot be served consistently with respect for such state interests, will suffer major damage if the state law is applied.” United States v. Yazell, 382 U. S., at 352 (emphasis added). The full force of this rule applies no less when the property in question consists of federally created benefits. De Sylva v. Ballentine, supra, at 580-582. Cf. Wallis v. Pan American Petroleum Corp., 384 U. S., at 68.
Consistently with this principle, the cases that have held that a State’s community property law was pre-empted have depended upon specific provisions in the federal statute governing the ownership of the property involved and, as well, upon a finding that application of the state law would substantially disserve demonstrable federal policies. Wissner v. Wissner, 338 U. S. 655; Free v. Bland, 369 U. S. 663. In Wissner, for example, the Court held that California could not treat the proceeds of a National Service Life Insurance policy as community property even though it assumed that the policy had been purchased with community assets. The decedent soldier in that case had, without obtaining his wife’s consent, designated his mother and father as the beneficiaries under his policy. The Court’s conclusion was based primarily upon a section of the National Service Life Insurance Act that specifically gave the insured the “right to designate the beneficiary or beneficiaries of the insurance” and “at all times” the “right to change” that designation. See 38 U. S. C. § 802 (g) (1946 ed.). From this explicit provision, the Court found that Congress had “spoken with force and clarity” in directing that the proceeds were to belong to the “named beneficiary and no other.” 338 U. S., at 658. California’s judgment awarding one-*596half of the proceeds to the wife, the Court said, would nullify the choice Congress had expressly given to the soldier, id., at 659, and frustrate the federal purpose of “enhanc[ing] the morale of the serviceman,” id., at 660. The Court also noted that the state-court judgment, insofar as it ordered the “diversion of future payments” as soon as they were paid to the beneficiary, was contrary to a provision in the Act protecting such payments from “seizure . . . either before or after receipt by the beneficiary.” Id., at 659.
In Free v. Bland, a treasury bond purchased by a husband with community assets designated the owner as husband “or” wife. Federal regulations explicitly provided that the survivor of an “or” form bond was to be the absolute owner. This directive, coupled with the substantial federal interest in establishing uniform rules governing the transfer of bonds, the Court found sufficient to override state community property law.
Essential to the finding of pre-emption in the Wissner and Bland cases was a determination that the ownership of the asset involved had, by express federal directive, been defined in a manner inconsistent with state community property law. In each case, explicit provisions of federal law not only conflicted with principles of state law but also created property rights at variance with the rights that normally would have been created by local property law.2
*597III
In the Railroad Retirement Act of 1974 Congress did not with “force and clarity” direct that the employee’s pension benefits should not be subject to the substantive community property law of California.
A
The Railroad Retirement Act contains no express provisions governing the ownership rights that may or may not attach to the pension interest of a married employee. The provisions governing the basic annuity are in themselves neutral. Both 45 U. S. C. § 231a (a)(1), which defines the eligibility requirements for the employee’s annuity, and § 231b, which contains the provisions governing the computation of annuities, state simply that the annuity is that “of the individual” employee. This indication that the benefit belongs to the employee is in this context wholly unremarkable. The congressional decision to “title” this federal benefit in the worker cannot, without more, be taken as evidence that Congress intended to disturb a body of state law that obtains whether or not the asset was earned by or is titled in one or the other spouse.
The benefit structure of the Act is also neutral. To be sure, Congress has chosen to provide a separate and additional benefit for spouses of retired workers, 45 U. S. C. § 231a (c) (3)(i), and to terminate that benefit upon divorce. 45 U. S. C. § 231d (c)(3). These provisions, however, do not preclude a rule of state property law that treats an annuity payable to either spouse as an asset of the marital community. *598The congressional decision to terminate the separate spousal benefit upon divorce in no way conflicts with that rule, for the community property interest — apart from the fact that it is an ownership interest and not a “benefit” for a divorced spouse — attaches only to that portion of an annuity attributable to labor performed during the marriage. And the provision of the separate and additional spousal benefit surely does not itself indicate an intent to displace community property law. The legislative history demonstrates quite clearly that Congress created this benefit in 1951 in order to respond to the greater financial needs of retired workers who are married. H. R. Eep. No. 976, 82d Cong., 1st Sess. (1951). The original Act afforded an annuity only for the individual employee. The amount of the benefit was tied to length of service and to salary, with no account taken of marital status upon retirement. See Report of the Commission on Railroad Retirement, H. R. Doc. No. 92-350, p. 7 (1972). When Congress increased the amounts available to employees with families by providing benefits for spouses, its purpose was simply to increase the level of benefits for employees with families, not to ordain the ownership of property within the family.
B
The only provision in the Act that even arguably might conflict with California community property law is § 231m, the anti-attachment provision. It states:
“Notwithstanding any other law of the United States, or of any State, territory, or the District of Columbia, no annuity or supplemental annuity shall be assignable or be subject to any tax or to garnishment, attachment, or other legal process under any circumstances whatsoever, nor shall the payment thereof be anticipated.”
Yet this language certainly does not speak to substantive ownership interests that may or may not exist in annuities or *599pension payments. Like similar language often included in spendthrift trusts, it seems to have been designed to protect the benefits from the reach of creditors. See generally E. Gris-wold, Spendthrift Trusts (2d ed. 1947). The provision thus has no real relevance to the question whether the annuity is the property of the marital community.3 For under community property law, the husband and wife are not one another’s creditors; they are co-owners. Upon dissolution of the marital community, the community property is divided, not adjudicated as indebtedness.
Neither the prohibition against “garnishment” nor that against “attachment” bears on an action to enforce a community property decree. Both terms govern remedies, not ownership rights, and the remedies themselves traditionally have been unavailable in an action grounded upon the theory that the property at issue “belongs” to- the claimant. See generally J. Rood, Law of Garnishment (1896); S. Kneeland, Law of Attachments (1885).4 The prohibition against “as*600signment” of pension payments is equally irrelevant to the question in this case. A determination that a particular asset is community property is clearly not an “assignment” of that property from one spouse to another. It is no more than a conclusion that the property interest — from the moment it arose — belonged equally to the two parties to the marriage. Principles § 97.
It is no doubt for these reasons that the Court places no great reliance on the “garnishment,” “attachment,” or “assignment” provisions of § 231m. The Court does, however, discern a major conflict between the clause prohibiting “anticipation” of payments and the California community property law. Yet it seems to me demonstrably clear that this provision of § 231m is no more relevant to the issue in this case than the “garnishment,” “attachment,” and “assignment” provisions.
There is, as the Court acknowledges, no legislative history to explain the meaning of the “anticipation” restraint in the *601Railroad Retirement Act. It can only be assumed, therefore, that Congress intended that it was to operate, as at common law,5 to ensure that the trustees of the fund would not make or be compelled to make lump-sum payments inconsistent with the periodic benefits provided by statute. See Griswold, supra, § 512. Like the other terms of § 231m, its import is thus procedural, not substantive. Griswold, supra, § 512.
The Court suggests that the “anticipation” restraint conflicts with California community property law because state law permits a court, upon dissolution of a marriage, to consider the value of benefits that are not yet due and then to make the actual award of community property out of other assets that are currently available. The reasoning seems to be that if an employee cannot “anticipate” benefits by securing a lump-sum award, the employee’s spouse is similarly prevented from “anticipating” a community property interest by receiving assets of equal value from the marital estate. This reasoning ignores the express wording of § 231m. The clause prohibits anticipation of “the payment” of a pension or annuity. A state judgment that considers the value of the pension interest acquired during marriage and satisfies that interest by ordering the transfer of other community assets does not anticipate a pension “payment.” There is, accordingly, no conflict between such a judgment and § 231m, for it has no impact at all upon the timing of payments to the em*602ployee and is therefore not at all incompatible with the distribution system established by Congress.
The Court also suggests that the “no anticipation” provision of § 231m was designed to preserve congressional “freedom to amend the Act.” Yet it has never been established that Congress is free to terminate or reduce the benefits afforded by the railroad retirement system. Unlike the Social Security Act, see Flemming v. Nestor, 363 U. S. 603, 608-611, the Railroad Retirement Act contains no express provision permitting Congress to terminate it. Indeed, the legislative history of the Act suggests that it was established to provide security to railroad workers whose benefits under private pension programs had frequently been treated .as discretionary payments. See H. R. Rep. No. 1711, 74th Cong., 1st Sess., 10-11 (1935). The drafters of the original legislation expressly stated that one of the important features of any retirement plan was a guarantee to the worker of an “absolute” right to receive the pension. Id., at 11. It thus seems obvious that the “no anticipation” provision — included as it was in the 1935 version of the Act — had no relationship whatever to any possibility that Congress might try to terminate or reduce the benefits payable under the Act. Whether Congress could ever do so is an open question, a question neither presented nor properly to be decided in the present case.
Finally, the Court suggests that “anticipation” would harm an employee who leaves the industry before retirement and thus is unable to “regain” the amount of the offset. But this difficulty becomes wholly imaginary when the nature of the community property award is understood. A spouse receives only one-half the value of the pension interest , attributable to work performed by the other spouse during the marriage. The “current connection with industry” requirement for supplemental benefits referred to by the Court obtains at the time the employee becomes eligible for current pension payments. If the employee is still working at the time the marriage is *603dissolved, a California court would be obligated to give heed to the benefit provisions of the Act in appraising the value of the interest acquired by the employee’s spouse during the marriage. And surely occasional problems in assessing the precise value of the community property — problems with which the courts of California routinely deal — cannot provide a basis for the Court’s finding of pre-emption.6
IV
The Railroad Retirement Act, unlike the statutes involved in Wissner v. Wissner and Free v. Bland, thus contains no evidence that Congress intended to withdraw the benefits at issue from the reach of California community property law. Believing, as I do, that the pre-emption perceived by the Court is entirely of its own making, I respectfully dissent.
This rule obtains regardless of the relative wealth of the parties. As stated in an early compilation of the Spanish civil law:
“Although the husband may have more than the wife, or the wife more than the husband, in realty or in personalty, let the fruits be common to both.” Novísima Recopilación, Book 10, Tit. 4, Law 3, quoted in Principles § 66, p. 143 n. 72.
The Court suggests that the benefits here “more closely parallel” the federal homestead land at issue in McCune v. Essig, 199 U. S. 382, than those involved in Wissner and Bland. Ante, at 582, The pre-emption principles applied in McCune, however, were no less rigorous than those articulated in the more recent cases. In McCune, a husband and wife had settled land subject to the homestead laws, and the husband had filed an appropriate claim. He died intestate before a patent was issued. Under the intestate laws of Washington, a community property State, the husband's interest would have passed to his daughter. Two provisions in the Homestead Act, however, established specific rules governing the method of completing a claim. One gave to the widow the right to fulfill the settlement terms and the entitlement to the patent. 199 U. S., at 388, *597389. Another expressly provided that the fee was to “inure to the benefit of” children only if the mother and father were dead. Id., at 389. Noting that “[i]t requires an exercise of ingenuity to establish uncertainty in these provisions,” the Court held that Washington law could not apply to reverse the order of ownership established in the statute. Ibid. In McCune, then, no less than in Wissner and Bland, the Court based its finding of pre-emption upon federal provisions that were “express” and “clear.”
Wissner v. Wissner, 338 U. S. 655, is not to the contrary, The Court did not there hold that the anti-attachment clause in the National Service Life Insurance Act had an effect on the substantive ownership interest in the proceeds. The Court simply reasoned that Congress might have included the clause in order to protect the serviceman’s unrestricted choice of beneficiary. That choice was clearly established in a different and “controlling” provision of the Act. Id,., at 658.
The 1975 amendment to the Social Security Act permitting those to whom alimony or child-support obligations are owed to garnish federal benefits to satisfy their claims, 42 U. S. C. § 659, hardly transforms these terms of §231m into provisions that bear on the ownership of railroad retirement benefits. Section 659 was enacted as part of a general bill designed to keep dependents of solvent but unwilling parents receiving federal benefits off the welfare rolls. S. Rep. No. 93-1356, pp. 42-43 (1974). With respect to actions for the enforcement of family-support obligations, the new provision waives the sovereign immunity of the United States and overrides contrary provisions in federal social insurance and retirement statutes. There is, however, nothing in either its language or legislative history to suggest that Congress, when it enacted § 659, intended *600to make a statement about substantive property rights that might generally affect the various federal benefit systems.
Such an intent is not to be found either in the 1977 definitional amendment to § 659, in which Congress expressly stated that “alimony” was not meant to include payments or transfers “in compliance with any community property settlement.” On its face, the amendment, §462 (c), simply states a legal truism. An alimony award is entirely distinct from a community property settlement. The only legislative history to explain the definitional amendment is the sponsor’s statement that its intent was merely to clarify. 123 Cong. Rec. 12913 (1977). The Court acknowledges that before the amendment some decisions had construed the “alimony” exception to encompass community property awards. Ante, at 587 n. 20. One might infer, therefore, that the amendment had the limited purpose of restating the obvious in order to quell unnecessary litigation. Whatever its purpose, it is clear that § 462 (e) could not have been intended to insulate railroad retirement benefits from the reach of state community property law. Addressed as it is to a provision waiving the immunity of the Federal Government to suit, it can mean no more than that a claimant under a community property award cannot proceed directly against the United States.
This type of restraint is thought to have been developed, in the late 18th century as a means of protecting the separate equitable estate of a married woman. Hart, The Origin of the Restraint Upon Anticipation, 40 L. Q. Rev. 221 (1924). It prevented the trustee of her estate from making income payments before they were due or from honoring transfers by the beneficiary that would have had the effect of forcing such payments and thereby dissolving the trust established for her protection. Ibid. In the modern spendthrift trust, it has the similar function of preventing the trustee from making lump-sum payments in derogation of the periodic payments or time restrictions provided for in the trust instrument. See E. Griswold, Spendthrift Trusts §512 (2d ed. 1947).
The Court also observes that “anticipation” of a community property interest would harm the employee to the extent that the award to the employee’s spouse might exceed the lump-sum benefits payable to the employee’s heirs should the employee die before collecting benefits. But survivor benefits payable under the Act are wholly distinct from the community property interest involved here.