MR. JUSTICE STEVENS delivered the opinion of the Court.
The question presented by the Secretary's appeal is whether Congress may condition an alien's eligibility for participation in a federal medical insurance program on continuous residence in the United States for a five-year period and admission for permanent residence. The District Court held that the first condition was unconstitutional and that it could not be severed from the second. Since we conclude that both conditions are constitutional, we reverse.
Each of the appellees is a resident alien who was lawfully admitted to the United States less than five years ago. Appellees Diaz and Clara are Cuban refugees who remain in this country at the discretion of the Attorney General; appellee Espinosa has been admitted for permanent residence. All three are over 65 years old and have been denied enrollment in the Medicare Part B supplemental medical insurance program. They brought this action to challenge the statutory basis for that denial. Specifically, they attack 42 U.S.C. 1395o (2) (1970 ed., Supp. IV), which grants eligibility to resident citizens who are 65 or older but denies eligibility to comparable aliens unless they have been admitted for permanent residence and also have resided in the United States for at least five years. Appellees Diaz and Clara meet neither requirement; appellee Espinosa meets only the first....
There are literally millions of aliens within the jurisdiction of the United States. The Fifth Amendment, as well as the Fourteenth Amendment, protects every one of these persons from deprivation of life, liberty, or property without due process of law. Even one whose presence in this country is unlawful, involuntary, or transitory is entitled to that constitutional protection.
The fact that all persons, aliens and citizens alike, are protected
the Due Process Clause does not lead to the further conclusion that all
aliens are entitled to enjoy all the advantages of citizenship or,
indeed, to the conclusion that all aliens must be placed in a single
homogeneous legal classification. For a host of constitutional and
statutory provisions rest on the premise that a legitimate distinction
between citizens and aliens may justify attributes and benefits for one
class not accorded to the other; and the class of aliens is itself
multitude of persons with a wide-ranging variety of ties to
In the exercise of its broad power over naturalization and immigration, Congress regularly makes rules that would be unacceptable if applied to citizens. The exclusion of aliens and the reservation of the power to deport have no permissible counterpart in the Federal Government's power to regulate the conduct of its own citizenry. The fact that an Act of Congress treats aliens differently from citizens does not in itself imply that such disparate treatment is "invidious."
In particular, the fact that Congress has provided some welfare benefits for citizens does not require it to provide like benefits for all aliens. Neither the overnight visitor, the unfriendly agent of a hostile foreign power, the resident diplomat, nor the illegal entrant, can advance even a colorable constitutional claim to a share in the bounty that a conscientious sovereign makes available to its own citizens and some of its guests. The decision to share that bounty with our guests may take into account the character of the relationship between the alien and this country: Congress may decide that as the alien's tie grows stronger, so does the strength of his claim to an equal share of that munificence....
For reasons long recognized as valid, the responsibility for regulating the relationship between the United States and our alien visitors has been committed to the political branches of the Federal Government. Since decisions in these matters may implicate our relations with foreign powers, and since a wide variety of classifications must be defined in the light of changing political and economic circumstances, such decisions are frequently of a character more appropriate to either the Legislature or the Executive than to the Judiciary. This very case illustrates the need for flexibility in policy choices rather than the rigidity often characteristic of constitutional adjudication. Appellees Diaz and Clara are but two of over 440,000 Cuban refugees who arrived in the United States between 1961 and 1972. And the Cuban parolees are but one of several categories of aliens who have been admitted in order to make a humane response to a natural catastrophe or an international political situation. Any rule of constitutional law that would inhibit the flexibility of the political branches of government to respond to changing world conditions should be adopted only with the greatest caution. The reasons that preclude judicial review of political questions also dictate a narrow standard of review of decisions made by the Congress or the President in the area of immigration and naturalization....
The cases on which appellees rely are consistent with our conclusion that this statutory classification does not deprive them of liberty or property without due process of law.
Graham v. Richardson, 403 U.S. 365 , provides the strongest support for appellees' position. That case holds that state statutes that deny welfare benefits to resident aliens, or to aliens not meeting a requirement of durational residence within the United States, violate the Equal Protection Clause of the Fourteenth Amendment and encroach upon the exclusive federal power over the entrance and residence of aliens. Of course, the latter ground of decision actually supports our holding today that it is the business of the political branches of the Federal Government, rather than that of either the States or the Federal Judiciary, to regulate the conditions of entry and residence of aliens. The equal protection analysis also involves significantly different considerations because it concerns the relationship between aliens and the States rather than between aliens and the Federal Government.
Insofar as state welfare policy is concerned, there is little, if any, basis for treating persons who are citizens of another State differently from persons who are citizens of another country. Both groups are noncitizens as far as the State's interests in administering its welfare programs are concerned. Thus, a division by a State of the category of persons who are not citizens of that State into subcategories of United States citizens and aliens has no apparent justification, whereas, a comparable classification by the Federal Government is a routine and normally legitimate part of its business. Furthermore, whereas the Constitution inhibits every State's power to restrict travel across its own borders, Congress is explicitly empowered to exercise that type of control over travel across the borders of the United States....