THE BILL WITH the money for the international development banks, the key providers of capital and technology to the global poor, is about to hit the House floor, and it is in trouble. In committee, close to $1 billion was cut from the $3.6 billion the administration sought. An effort to cut more may be made and there also may be moves to attach restrictive amendments, in particularly an amendment to prevent the World Bank and its regional counterparts from lending to Vietnam.

At a time when the country is eager both to pep up the American economy and calm down the Third World, it is hard to understand why legislators would wish to indulge in ritualistic flagellation of these particular instruments of aid. For each dollar the United States actually contributes to the banks, as distinct from a dollar put up as a guarantee, two to three are spent in this country for procurement. And since American contributions unlock private investments and official contributions by others, each contributed dollar ends up producing perhaps $50 in loans. Some congressman persist in seeing all forms of foreign aid as a "giveawat." Actually, aid is a form of control: It provides poor countries with a way to handle the pressures that could otherwise explode and make the Third World an even more difficult environment for the United States than it already is. Humanitarianism and brotherly feeling are not the only reasons aid is compelling. American political self-interest is a compelling reason too.

It is bad enough that, by virtue of the cuts already voted in committee, American leverage in the banks - not to speak of the banks' lending authority - has been diminished. American leverage would be diminshed even more if the House were to add some of the restrictive amendments that the Appropriations Committee, in its wisdom, passed over. There is a certain support, though perhaps not so much as in previous years, for amendments that would either tie loans to human rights or halt loans helping countries produce commodities that cut into American sales of the same commodities.But the amendment with the most potential steam behind it seems to be one that would keep the banks from lending to Vietnam.

All of these amendments are bad: They represent an attempt to impose a unilateral American policy on a multilateral institution. Since the banks' charters prevent them from accepting earmarked or conditional funds - how could a multilateral bank function on any other basis? - amendments would cost the banks all of the amender's contributions and would force a costly recalculation of the formulas by which other nations contribute.

In the specific case of Vietnam, there is a further consideration: The banks have already stopped lending to Vietnam . They stopped, on grounds that a country engaged in an invasion could not be properly attentive to development, after Vietnam invaded Cambodia. The World Bank now frankly says it does not plan to offer loans to Vietnam. It would, therefore, be gratuitous for the House to tack on an anti-Vietnam amendment. Such an amendment would simply make it impossible for the banks to accept Americans funds for countries that Congress does want to lend to.What could hurt American interests more?