The great "red" scare of 1986 is over. The president and Pat Buchanan have backed off the claim that those who want to end the contra resistance would ensure the success of communism in Nicaragua. The tone of the charge was uncomfortably accusatory. But that does not make the proposition any less true this week than last.

It seems to me an unexceptionable and rather undeniable fact: if the contras wither, as House Democrats devoutly wish, there will be an irreversible consolidation of Sandinista power in Nicaragua. Can anyone present a remotely plausible scenario in which the Sandinistas, unforced, either relinquish power or permit a free competition for power -- i.e., a democratic election?

That does not mean that those who are against contra aid want to see a communist Nicaragua. But the consequence of their position, however unintended, is certainly not unforeseen.

So it is dismissed. America's national interest, it is said, depends not on the form of a foreign government, but on its foreign policy. What we want is a Nicaragua that doesn't subvert its neighbors or permit the Soviets a military base. We don't care how it is ruled. Therefore the United States should work out a deal with the Sandinistas -- a negotiated "Contadora" agreement under which the Sandinistas guarantee not to bother us or their neighbors, and we guarantee them control of Nicaragua by cutting off their opponents.

Now, what will prevent the Sandinistas from violating such an agreement? In 1979 in return for hemispheric support, the Sandinistas pledged in writing to the Organization of American States to bring pluralism and democracy to Nicaragua. They got the support. They gave Nicaragua dictatorship.

Apart from their word as Leninist gentlemen, what is to prevent the Sandinistas from ultimately subverting, for example, Costa Rica? Or from bringing in Soviet MIGs and transports and submarines, quietly and gradually, exactly as Cuba has done for 25 years?

Bruce Babbitt, progressive, hard-headed, neo- liberal Democrat, and an advocate of such a deal, has the answer. "The United States, with its overwhelming dominance of the hemisphere, has the power and the duty to enforce such an agreement," he writes in The New York Times.

American power. It seems, then, that the Marines will do the enforcing. So it is unanimous. Everyone agrees: cut off the Nicaraguans who want to fight the Sandinistas and the only cordon against Sandinista threats to regional and U.S. security will be American boys and American blood. Not very sanitaire. And this is advertised as a counsel of prudence.

The current contra debate has produced the clearest division of the house in memory. The Democrats want to deal with the Sandinistas and the president wants to get rid of them. What muddies the waters is that neither side is permitted to say what it really thinks.

Democrats have to pretend that they care about democracy in Nicaragua. And the administration must pretend it does not seek to overturn the Sandinistas. Democrats accuse the president of seeking a military solution, as if that would be undesirable. (It certainly did the trick for Castro in Cuba, for the United States in Grenada and, for that matter, for the allies in World War II.) Even more absurd, the administration is forced to agree that victory is not its objective.

Instead, it has to cook up another preposterous mission on which to send Phil Habib. This one is designed to symbolize for House Democrats the administration's desire for a diplomatic solution. To be sure, House Democrats are easily impressed by airborne symbols. Last year, after all, a single flight to Moscow by Daniel Ortega convinced them that this agrarian reformer had pro-Soiet proclivities.

And now there is on-again, off-again talk of a compromise: the United States will starve the contras for a few more months, and the Sandinistas will thereby be induced to compromise and negotiate. This is the Nicaraguan version of that memorable Vietnam success, the "bombing pause." Only this time, the bombing -- deadly fire from Afghan-tested Soviet MI-24 helicopter gunships -- will continue. The pause will be in the supply of anti-aircraft defenses for those on the receiving end.

Compromise or not, if in the end the contras are cut off, the reason ultimately will be fear -- fear of another Vietnam. It will not be the first time we have closed our eyes to a threat to escape an evil d,ejd see it as another Gulf of Tonkin Resolution. They might consider another analogy, the Neutrality Acts of the 1930s, by which Congress undertook to legislate American safety in a world of Nazism and Japanese militarism. After the passing of the Third Neutrality Act of 1937, the New York Herald Tribune wryly dubbed it "an act to preserve the United States from intervention in the war of 1917-1918."

Cutting off the contras will not repeal the Gulf of Tonkin Resolution. Nor will it bring us the blessings of neutrality. At least the isolationists of the '30s had an idea: hunkering down and hiding from the world in our own hemisphere. Where do we hide now?