JIMMY CARTER had something appropriately direct and harsh to say yesterday about Moscow's intervention in Afghanistan. If airlifting in thousands of Soviet troops to murder the established leader and to seat a tame Afghan who's been on hold in Prague is not "gross interference," what is? Mr. Carter, who had no other response yesterday (unless you count the dispatch of the undersecretary of state to Europe), could scarcely have said less.

But, frankly, it was not Jimmy Carter's voice that we were waiting to hear, or not only Jimmy Carter's. It was the voice of the "nonaligned" countries -- that large group of nations supposedly ever and impartially alert to guard the independence of theircompany from the machinations of both great powers. Who, after all, has the most to fear from an operation in which Moscow smuggles in troops under the guise of helping one leader, overthrows him and installs another? This may be a geopolitical embarrassment to the United States; certainly it demonstrates a Soviet intervention capability alarming both in logistics and boldness. But it is a far more ominous threat to any number of Third World rulers, who could all too easily find their political rivals being similarly exploited by the Kremlin. It is, in brief, the Third World that should be protesting the loudest. In particular, it should be the Moslem world, which regards Afghanistan as one of its own and which is the likeliest field in which Moscow will want to continue to play.

As for the Soviets in Afghanistan, we wish them ill. The old regime was having great trouble coping with a rebellion of Moslem tribesmen protesting against modernization Soviet-style. The new regime, which must labor under the handicap of being even more conspicuously an anti-Islamic Soviet puppet, inherits that struggle. The tribesmen have been getting help where they can from other Islamic countries. Perhaps more help will be forthcoming from Islamic quarters now. The United States evidently has withheld support, direct and indirect, from the tribesmen. These latest events, however, may force the administration to review its Afghan hand. This is quite apart from what Moscow's intervention will do to the American defense debate and to the general international tone.

Clearly, Moscow took the occasion of the United States' distraction in Iran to carry off its Afghan Putsch. But the United States' cannot afford to let the central beam of its policy move away from the hostages. Mr. Carter reported yesterday that the United States is pushing immediately in the Security Council for economic sanctions against the Khomeini regime -- a project no less worthy for being in peaceable contrast to the Kremlin's use of raw power in Kabul. Once that project is launched, the administration will presumably be in position to take the Soviet intervention in Afghanistan to the United Nations, too. But meanwhile -- we say it again -- it would be interesting to hear from the so-called nonaligned.