procedural safeguards of due process .... But that the formulation of these policies is entrusted exclusively to Congress has become about as firmly imbedded in the legislative and judicial tissues of our body politic as any aspect of our government.... We are not prepared to deem ourselves wiser or more sensitive to human rights than our predecessors, especially those who have been most zealous in protecting civil liberties under the Constitution, and must therefore under our constitutional system recognize congressional power in dealing with aliens.... Id. at 531-32, 74 S.Ct. 737. To that end, the Court has applied a very lenient “facially legitimate and bona fide reason standard” to constitutional challenges of immigration statutes. See, e.g., Fiallo, 430 U.S. at 795, 97 S.Ct. 1473 (<HOLDING>); Kleindienst, 408 U.S. at 769, 92 S.Ct. 2576
holding that a statute may be facially challenged only  by establishing that no set of circumstances exists under which the statute would be valid ie that the law is unconstitutional in all of its applications or at least that the statute lacks a plainly legitimate sweep  holding that immigration statute that distinguished between legitimate and illegitimate children of united states citizens in giving preference for immigration status to aliens met equal protection standards because distinctions in statute were based on facially legitimate and bona fide reason holding that aliens constitute a specific minority deserving enhanced judicial protection and making alienage a suspect classification under the equal protection clause of the united states constitution recognizing equal protection right of illegitimate children to maintain civil action for nonsupport against parent holding both legitimate and illegitimate children to be proper claimants under georgia wrongful death statute