concurring.
In light of my Brother Douglas’ assertion, post, at 508, that today’s disposition might be taken to impair the integrity of the “rule of four,” see Ferguson v. Moore-McCormack Lines, 352 U. S. 521, 559-562, 564 (1957) (opinion of this writer), I deem it appropriate to set forth my reasons for joining in the dismissal of the writ as improvidently granted.
*498The Federal-Aid Highway Act of 1968 provided in pertinent part that:
“The Secretary [of Transportation] shall not approve any project [such as that here involved] which will cause the displacement of any person . . . unless he receives satisfactory assurances from the State Highway department that—
“(3) within a reasonable period of time prior to displacement there will be available, to the extent that can reasonably be accomplished, in areas not generally less desirable in regard to public utilities and public and commercial facilities and at rents or prices within the financial means of the families and individuals displaced, decent, safe, and sanitary dwellings, as defined by the Secretary, equal in number to the number of and available to such displaced families and individuals and reasonably accessible to their places of employment.” 23 U. S. C. § 502 (1964 ed., Supp. V).
The principal issue presented by this case is whether that statute, either of its own force or together with the administrative regulations promulgated pursuant to it, prevents the Secretary from authorizing construction of a segment of the interstate highway system, even where the rights-of-way had been acquired and some persons displaced prior to the effective date of the 1968 Act, unless the State first compiles a comprehensive formal relocation plan. In short, the question is what constitutes “satisfactory assurances” in such a case.
Since certiorari was granted, a number of events have occurred that, in my judgment, have rendered this case wholly inappropriate for our review. First, the Act upon which petitioners base their case has been repealed. Secondly, a new statute has been enacted by the Congress *499that alters drastically the potential impact of any decision we might reach in this case. Third, we were informed that, as of the date of oral argument, less than 10 persons remained to be displaced by this federal project. Finally, in their brief on the merits in this Court, petitioners have almost completely abandoned their original claim for relief and now seek to broaden substantially the nature of the remedy they seek.
The original prayer for relief simply sought to enjoin further displacement pending submission and implementation of a formal relocation plan by the West Virginia State Highway Department. The fact that the statute has been repealed since certiorari was granted and that less than 10 persons would be affected were we to accept petitioners’ legal position renders this case, I think, a classic instance of a situation where the exercise of our powers of review would be of no significant continuing national import. Of course, every individual alleging he has been abused by the exercise of federal power should, as a general matter, be heard, even where his situation becomes unique due to repeal or cessation of the action he challenges. That is why federal district courts and courts of appeals are provided and vested with largely obligatory jurisdiction. Hearing such claims is not, however, a principal purpose for which this Court sits. See Rule 19 of the Rules of this Court.
At the same time Congress repealed the 1968 Act it enacted the Uniform Relocation Assistance and Real Property Acquisition Policies Act of 1970. 84 Stat. 1894. Its principal purpose, as the title implies, was to establish a uniform governing rule of federal law for all federally directed and federally financed projects that cause displacement of persons and businesses. The 1970 Act was very consciously modeled on the 1968 Federal-Aid Highway Act, following “as closely as possible [its] substantive provisions,” S. Rep. No. 91-488 (1969), in an *500effort to assure that all persons uprooted by federal authority would receive the beneficent protection earlier extended to those situated in the path of highway construction. See especially 115 Cong. Rec. 31535 (remarks of Sen. Cooper). Section 210 of the new Act provides that:
“[T]he head of a Federal agency shall not approve any grant to ... a State agency, under which Federal financial assistance will be available to pay all or part of the cost of any program or project which will result in the displacement of any person on or after the effective date of this title, unless he receives satisfactory assurances from such State agency that—
“(2) relocation assistance programs offering the services described in section 205 shall be provided to such displaced persons;
“(3) within a reasonable period of time prior to displacement, decent, safe, and sanitary replacement dwellings will be available to displaced persons in accordance with section 205 (c)(3).”
Section 205 (c) (3) describes in some detail the services that must be provided. It does not, however, explicitly state that such “program” shall include a comprehensive plan reflecting the projected relocation of each individual affected.
Arguably, the presence of this provision would enhance the general significance of our construction of the relevant,1 and similarly worded, section of the 1968 Act. *501Indeed, my Brother Douglas asserts that “any necessary interpretation of the 1968 [Act] would be equally applicable to the 1970 Act.” Post, at 504, n. 1. For me, however, this does not increase, but rather further diminishes, the appropriateness of our ruling in the instant case.
This case comes to us on a record that sheds light only upon the proper construction of the 1968 Act which governed only federal programs, administered by one agency, that aid highway construction by the States. It now appears that anything we might hold in that regard may very well have to be carried over in full force to govern the administration of the large number of federal programs that bring about human displacement. To render our determination upon such a wide-ranging issue we should, at a minimum, have the benefit of the thinking of lower federal courts on this problem, as well as some knowledge of the responses of the various affected agencies to this new statute. Yet we are entirely without these essential aids.
To the extent, then, that the instant case has any significance for the future, it seems to me that such issues should await a case arising under the new statute. Insofar as the case can be said to present an issue only as to the proper construction of the 1968 Act, events subsequent to the granting of the writ have, as noted previously, robbed it of all national significance.
Finally, it is troublesome that petitioners have virtually abandoned their initial claim for relief. Instead of the preparation of a plan,2 they now seek a decree to the effect that the District Court should bring before it all *502persons displaced by the highway and inquire whether their new locations meet statutory standards. As to this issue, there is neither an opinion below nor a record upon which to judge the claim. The case was tried upon a theory that the statutes require a formal plan, not that numerous individuals had been improperly relocated in fact. And there would seem to be no bar to the initiation of subsequent proceedings, in the District Court, raising individual claims of this sort where they do exist.
In light of this changed posture of the case, I do not think its adjudication would be a provident expenditure of the energies of the Court. Cf. Sanks v. Georgia, 401 U. S. 144 (1971).
The 1968 Act is still the relevant focus of this class action. The 1970 Act did not become effective until January 1971, and it specifically preserves rights and liabilities existing under prior Acts. § 220 (b). Those petitioners not relocated prior to the effective date of the 1970 Act may have a claim under the latter statute as well.
Petitioners have not wholly abandoned their original claim for relief. They argue that preparation of a plan “may be appropriate relief” for those not yet relocated. Petitioners’ Brief 51. Prime emphasis, however, is placed upon the new remedial technique described in the text.