In August the four democratic presidents of Central America and dictator Daniel Ortega of Nicaragua signed a peace plan. Its objective is to move the struggle for democracy from the battlefield to the political arena, and in the process achieve peace -- peace as a result of democratization and not merely as a result of ending war.

This is how Central Americans understand the plan, and why the Nicaraguan resistance accepted it. But now the United States is moving to stop aid to the resistance, without conditioning that action on Sandinista compliance with the accord. Such a policy will result in military victory for the Soviet-backed Sandinista army and have inescapable consequences for Central America and the United States.

When I left Nicaragua in May 1982, La Prensa was publishing, Archbishop Obando y Bravo was speaking over Radio Catolica, opposition parties were functioning and some 3,000 political prisoners were held in jail. Two months before that, the state of emergency had been reimposed on the country. As Ortega explained to a restricted Cabinet meeting: "The worst mistake the Sandinista Directorate has made since July 1979 was the lifting of the state of emergency after Somoza's downfall; we now have an excuse to reinstate it and the military means to enforce it."

Within 60 days the restricted liberties that existed before March 1982 were all but officially scrapped. I made the decision to leave the revolution, convinced that totalitarian rule and Soviet-bloc ties were deeply rooted in the Sandinista group that had betrayed the democratic revolution for which I had struggled six years and endured jail, torture and exile.

I left my country with two haunting memories. One was of a military maneuver I witnessed, involving T-55 Soviet tanks, Soviet helicopters and Soviet heavy artillery, all directed by a Cuban general. The other was of the secret party-to-party agreement between the Communist Party of the Soviet Union and the Sandinista National Liberation Front, first signed in 1980 and renewed year after year. But I left with faith in the hemispheric democracies, which had been instrumental in bringing down the Somoza regime.

Now I see that to comply with the peace plan, the Sandinistas reopen La Prensa, let Cardinal Obando speak over Radio Catolica, talk to opposition political parties and talk of freeing a few of the by now 8,000 political prisoners and maybe even of lifting the state of emergency. And I cannot help remembering what I lived through back in 1982. The party-to-party agreement has been renewed for the seventh consecutive year, and there has been a breathtaking increase in the Sandinista Soviet-supplied arsenal. Unless Ortega thinks he lacks the military means to enforce it, he will find another excuse to reinstate the state of emergency for a third time.

This peace plan provides for ending war by two stages: first, an effective cease-fire, simultaneous with democratization measures and the halting of military aid to insurgent forces on Nov. 7; second, the laying down of arms by the resistance, once security agreements have been reached by the five governments, according to Point 7 of the peace plan. This implies maintenance of the resistance as a viable military force until the second stage is under way.

It is time to stop the partisan debate and support the peace plan with bipartisan actions before it is too late. The United States should provide the resistance with nonlethal aid for the next 18 months to prevent the Sandinistas from dragging their feet in the security negotiations of the second stage. Lethal aid should be provided if the Sandinistas do not comply with the accord by Nov. 7 -- including a cease-fire negotiated between them and the resistance, as defined by the president of Costa Rica.

I believe this is a real chance for peace with democracy. The Nicaraguan resistance has made its contribution by forcing the Sandinistas to sign the Central American peace plan. Now it is up to the United States to prevent another betrayal of the Nicaraguan people's aspirations. History will judge who gave peace a real chance. The writer is a former revolutionary official in Nicaragua who is now a member of the directorate of the Nicaraguan resistance. He resigned as president of the Central Bank of Nicaragua in May 1982.