THERE IS A fair consensus in Washington, or there used to be, that the United States acted reprehensibly when it used its influence in international financial institutions to "destabilize" the government in Chile in the early 1970s-by denying loans, credits and the like. Now some of the people most exercised by that effort urge the United States to use its influence in the same institutions to destabilize the government in Nicragua. This raises a question: If it is wrong to use an ostensibly apolitical institution like the World Bank or International Monetary Fund to squeeze a government of the left, why is it acceptable to squeeze government of the right, as group of legislators would like the IMF to do to Nicaragua in several loan votes due to be taken today?

Those favoring pressure on President Anastasio Somoza say that he runs a rotten and repressive regime and that the vote of approval implied by the loans, hardly less than the money, will bolster his misrule. They are quite right, both as to the nature of his regime and as to the effects extending the loans. Yet Nicaragua met the broad terms of the IMF when it joined and it evidently has met the specific terms the IMF has put forth for these drawings. There is an automaticity to the way the IMF and organizations like it work: You put money in and you can draw money out if you meet certain technical conditions. In a world composed of very different kinds of governments, the IMF could run no other way.

Last year the United States tried for a time to negotiate President Somoza out power and, to put on heat, it engineered the collapse of a routine IMF loan to Managua. This touch of politicization did not remove the Somoza dynasty. But it did arouse other member governments of the IMF. This time around, with no negotiation pending, a chastened Carter administration intends to let the loans go through. That leaves Mr. Somoza in power-a profoundly regrettable political fact. It also leaves the IMF free to do the essential ecomomic work it was set up to do.

The international system is stacked for the benefit of sitting governments. All of us may rue this at one time or another but, from the viewpoint of the common good, there is much to say for playing by the international rules.