Against the force of such considerations, we find respondents' countervailing arguments quite unpersuasive. Their basic contention is that United States courts could make a significant contribution to the growth of international law, a contribution whose importance, it is said, would be magnified by the relative paucity of decisional law by international bodies. But given the fluidity of present world conditions, the effectiveness of such a patchwork approach toward the formulation of an acceptable body of law concerning state responsibility for expropriations is, to say the least, highly conjectural. Moreover, it rests upon the sanguine presupposition that the decisions of the courts of the world's major capital exporting country and principal exponent of the free enterprise system would be accepted as disinterested expressions of sound legal principle by those adhering to widely different ideologies.

Without doubt there are great interests of society which justify withholding the coercive arm of the law from these duties of imperfect obligation, as they are called; imperfect, not because they are less binding upon the conscience than those which are called perfect, but because the wisdom of the social law does not impose sanctions upon them.