THE WAY it was agreed in 1972, the Soviets would move into their new embassy on Wisconsin Avenue at the same time the Americans moved into their new embassy in Moscow. Otherwise, the Soviet Union would get quick action out of private American contractors and the United States would have no leverage in dealing with the Soviet government's construction monopoly. The pros recognized that as the kind of toughness needed to negotiate successfully with the Kremlin.

So what happened? Well, the Russians wrote up their building plans promptly and had them promptly cleared in Washington. The Americans dragged on their plans and then got into a protracted dispute on the building contract. Let us start building, the Russians side then said. Fine, said the new Carter administration team, playing Mr. Nice Guy, but do provide us certain other interim facilities. The Russians built. But, for a year or more, they did not provide the extra facilities.And they still have not made it possible for a contract on the new American embassy to be drawn. So it is that the Russians have now completed six apartment buildings and more on Wisconsin Avenue and are clamoring to move their people in, and the Americans have not turned the first spade of dirt in Moscow.

It is a painful spectacle and, especially if the United States does not play it right from this point onward, it will make many Americans ask if the Carter administration is negotiating on SALT any more effectively than it has on the embassies. The Russians have behaved like Russians, turning American impatience and good will to their own advantage, exploiting every comma, frustrating and tiring their negotiating partners. But have the Americans behaved like . . . Americans? The Carter administration's decision to let the Russians start building first looks pathetic in retrospect. If the administration were to be equally "reasonable" now and to heed Soviet pleas to allow the new premises to be occupied, it would have only itself to blame for the inevitable adverse effect on its efforts to get approval for other deals it makes with the Russians.