"There is a plan to create a communist Central America which, if successful, will have momentous consequences for our security and that of our European allies, for Israel's international position and for the unfortunate people of Central America."

So wrote U.N. Ambassador Jeane Kirkpatrick in The Washington Post last Sunday. And because she is said to be the driving force behind administration policy-making for Central America, her analysis of the communist threat in that region can safely be taken as the harrowing rationale for whatever it is, exactly, that the president intends to say on that subject to a joint session of Congress this week.

Nicaragua is already long gone to Marxist-Leninism and is deep into the El Salvador insurgency, Kirkpatrick believes. It is hell-bent, in close collaboration with Cuba and the Soviet Union, on pressing communist revolutions up and down the Central American isthmus. The threat to Israel lies in Managua's "PLO connection." The threat to Europe is in the importance of Caribbean sea lanes to the Western allies.

Where Kirkpatrick comes a bit unglued is when she analyzes Congress. "Nobody talks about slippery slopes when we rush weapons to Thailand, (military) trainers to Lebanon or economic aid to Africa or Asia," she complains.

Why, she asks, is Congress so much more reluctant to help an "imperfect democratic government" in El Salvador than "much less perfect governments in more remote regions?" Is it, she wonders, because lobbies of the left have managed to make the anti-communist side "unfashionable"?

Kirkpatrick is barking up a familiar, neoconservative, wrong tree. There are simpler explanations for Congress' resistance to the president's military aid program for El Salvador and to "covert" U.S. support for the mini-insurgency in Nicaragua. Some of them lie in what's missing from her own argument.

Nothing in it, for instance, explains why the Other Side seems to do so well while Our Side is so vulnerable. We are left to wonder why all of those endangered "dominoes" are not rallying around effectively with their own countermeasures. Kirkpatrick's fixation on Congress reflects the administration's reliance on the escalating application of U.S. military and economic aid.

The short explanation, then, for why Congress is so skittish is the single- minded open-endedness of the administration's approach. For a more comprehensive explanation, I recommend the recent report issued by nearly 50 prominent Latin and North Americans who have been participating since last October in an Inter-American Dialogue under the co-chairmanship of Sol Linowitz (former U.S. ambassador to the Organization of American States) and Galo Plaza (who has been president of Ecuador and Secretary General of the OAS).

In polite language, the report constitutes a direct challenge to administration policy from a diverse group, including some Americans who hardly fit the "liberal" label that Kirkpatrick attaches to the administration's critics: retired Gen. David C. Jones, former chairman of the U.S. Joint Chiefs; Frank Shakespeare, Richard Nixon's director of the U.S. Information Agency; international banker David Rockefeller.

Much has been made of the "do's" of the report: a generalized call for what could only be considered a diplomatic spectacular. It would involve almost everybody concerned--including Cuba, Nicaragua and the Soviet Union. It would also presuppose considerable U.S. tolerance, in principle, of Marxist- Leninist regimes under clear "ground rules and monitoring procedures for self-restraint throughout the region."

The group is admittedly unsure of how you do this; its positive proposals are offered to "stimulate fresh thinking." But the strongest stimulant to fresh thinking is to be found in the "don'ts." In arguing for negotiations in El Salvador, for example, the report warns against an effort to solve the conflict in that country by military means.

Given the long history of U.S. intervention, overtly and covertly, in Central America, the report also recommends that this country "provide unmistakable assurances that the United States will refrain from reverting to these practices."

The group argues that, "Even where there is a military dimension to conflict, as in Central America, the solutions ultimately lie in economic and social development and political dialogue, not in weapons or military advisors."

The Linowitz-Plaza prescriptions probably would not commend themselves to most past U.S. administrations. The not-on-my-watch syndrome is a potent element in presidential calculations of the risks that can safely be taken of losing ground to communism. But the Inter-American Dialogue does offer more insight to the reservations the administration is encountering in Congress than Jeane Kirkpatrick's soft-on-communism theory of the case.