When the World War II victors asked themselves 40 years ago what values they had fought for, one led all the rest: the rule of law. Like World War I, of which it was in so many ways a continuation, the war of 1939-45 contested the outlaw claim that might makes right, and power writes its own law.

To reinforce the costly triumph over that old but unacceptable heresy, the United States was determined to pursue whatever steps human ingenuity could devise to strengthen international law. There was the founding of the United Nations, the brief flourishing of the World Federalist movement, and the U.S. determination to hold war- crimes tribunals. In those trials a standard of accountability would be laid down, and not by a sham, either.

In 1946, the United States at last adhered to the World Court at the Hague: a successful end to a battle first waged many years earlier by Republican statesmen such as Elihu Root and Charles Evans Hughes, and backed by GOP presidents from Harding on.

Now, by a disturbing irony, the 40th anniversary of the end of World War II finds the Reagan administration refusing to respond to complaints lodged at the World Court by Nicaragua. In briefs prepared by able U.S. lawyers, Nicaragua charges that in subsidizing the contras and in bluntly vowing to force a change of regimes in Managua, the United States is acting lawlessly. We respond -- though not formally, and not in court -- that Nicaragua, in aggression against El Salvador that we are not prepared to specify, is the outlaw.

To be sure, a World Court judgment on such tangled conflicts might be (as Lincoln said of a premature Emancipation Proclamation) "like the Pope's bull against the comet." But the merits of the dispute are secondary. Embarrassingly, the Reagan administration has declined to come into court and lay before an impartial international tribunal its defense against Nicaragua's accusations. In this we are behaving with the incivility of Khomeini's Iran, which five years ago refused to honor the World Court's condemnation of the illegal detention of our embassy personnel.

The excuses thus far offered at the State Department are self-serving. They can only bolster the impression that our case for subsidizing the contras or for a trade embargo is too feeble, in terms of the law we pretend to honor, to stand scrutiny.

We need to clarify for ourselves our responsibilities to a world menaced by lawless force. The gentle among us invariably welcome judges but no police. The Reagan administration, contrarily, seems to want police but no judges. No scheme of international law and order can conceivably work without both.

Our leaders at the end of World War II had no doubts about the obligations arising from its ruin and slaughter, and firmly put the United States behind as much international law as the jealousies of national sovereignty could digest. Now we seem content to sit among the scofflaws, Iran and the Soviet Union, giving the raspberry to the sheriff and the summons to court. On such an anniversary, it is more than an irony. It is a disgrace.