AT VENICE, President Reagan joined other representatives of the democratic nations in urging the World Health Organization to lead an international charge on AIDS. Back in Washington, the United States remains $118 million in arrears on its treaty-obligated assessments for that same World Health Organization, and it is similarly behind in what it has pledged to give to a key Latin AIDS combatant, the Pan American Health Organization. Across the whole range of United Nations activities and agencies -- in fact, across the whole range of programs for international development -- the United States cheats on its political interests and on its legal and moral obligations. Meanwhile, as at Venice, the administration hails the uses of the organizations that are deprived of American funds.

The U.N. and its specialized agencies came to be squeezed by a common executive-congressional desire to 1) force the U.N. system to become more efficient and more amenable to American purposes ("reform") and 2) cut the American budget. By general agreement in Washington and New York, some progress has been achieved toward the first goal, which is a worthy one. But budget considerations are still keeping the United States from making good on resuming full funding, which was to be the U.N.'s reward for undertaking reform. American good faith is at issue.

The squeeze on development can be traced back in part to these considerations. But more was at work here -- some flawed political choices made by both the administration and Congress. In fact, the United States increasingly has a three-countries-only foreign aid program -- and a program that places military over economic aid. Israel, Egypt and Pakistan get the lion's share, a politically privileged share that grows even as the shares of others shrink.

The aid program is now in a knot that Congress and President Reagan have been unable to agree how to untie. But there is an obvious (and urgent) way to do it: either raise the extra revenue to pay for important aid programs or redivide the available funds so as to give a larger amount to development aid and also to recipients without political guardian angels.