Only a few weeks ago it appeared we were headed straight for military intervention in El Salvador. Now, thanks to the press and various members of Congress, and to Secretary Haig's self-inflicted wounds, even the secretary, having at last listened to what the Mexicans have been trying to tell us, seems to have paused in his headlong charge. Perhaps we can use the breathing space to ask what it is that we are about.

Of 199 U.S. military hostilities abroad without a declaration of war between 1798 and 1972, no fewer than 81 took place in the Caribbean. Early in this century, we intervened there mainly because of our anti-Kaiserism. Since World War II we have intervened there mainly because of our anti-communism. Usually we have cried panic over the Panama Canal.

Thus our Caribbean policy has always swung on a wider hinge--the hinge of our global (and domestic political) concerns. Isn't it about time we devised a policy for the Caribbean itself? We have not had one since President Johnson killed the Alliance for Progress and President Nixon buried it.

Recently, President Reagan set forth what his trumpeters called a new Caribbean Basin Initiative. Its three main proposals were duty- free entry of Caribbean products into the United States (with certain limitations), incentives to U.S. private enterprise to invest in the Caribbean and supplemental aid.

But many Caribbean products already enter duty-free, and surely President Reagan knows it is highly doubtful that Congress will extend the list over the anguished outcries of domestic industries and labor unions. Surely he also knows that what we think of as investment looks to the peoples there like Yankee imperialism. Indeed, in many Caribbean countries, it is doubtful that U.S. private enterprise has much of a future at all--they don't want it. As for supplemental aid, most of it will go to El Salvador.

Reagan's whole new initiative is tightly tied to his Caribbean crusade against Nicaragua, Castro and the Salvadoran guerrillas. We pay heed to the Caribbean only when something goes wrong. We are the only great power that does not take its near neighbors seriously.

Now a new cycle of revolutions from below has begun. In Nicaragua, the Sandinistas have toppled Somoza. In El Salvador, they seem about to defeat the government we support. In Guatemala, the Indians are rising.

What are the causes of this trouble? They are simple. Indeed, they are one: injustice. In some places, 400 years of it. In some countries, out in the countryside, campesinos are poor even by Asian standards--they never see $50 a year, yet their transistor radios give them a hint of what life could really be. For intellectuals, and for campesinos come to the city, injustice means military repression. But always the root cause is that too few people have too much land and money; too many have too little.

Time and again we have had a chance to join these revolutions. Time and again we have defended the indefensible status quo. I can think of only one decisive turning point where we threw our weight solidly against dictatorship: when President Kennedy sent the fleet to the horizon off the Dominican Republic to force out the heirs of Trujillo.

But our present national debate is not addressed to that issue. Instead, it is addressed to whether foreign communists are or are not aiding the Salvadoran guerrillas. Haig sees a dark conspiracy running straight to the Salvadoran guerrillas from Nicaragua from Cuba from the Soviet Union. But Castro would seem to have more to gain from accommodation with the United States than from helping the Salvadoran guerrillas. The Soviet Union could scarcely be eager to take on a second Latin client like El Salvador.

Just how are these evil conspirators running the Salvadoran guerrillas from Managua? By radio? By telephone? By courier? By satellite or smoke signal? I have had some experience with small Caribbean countries, and the notion that an apparatus in Managua could direct the activities of guerrillas in the caves and mountains of El Salvador is simply laughable.

Behind the debate now going forward between the press and Capitol Hill, on the one hand, and Haig on the other, lies a dangerous assumption--that if indeed Haig can produce "irrrefutable" evidence that Nicaragua, Cuba and the Soviet Union really are aiding and directing the guerrilla movement in El Salvador, then of course we will be justified in intervening.

But that is the wrong question. We should be debating a political, not a military, solution to the Caribbean's troubles--policies to help shore up the vital center against the extreme right and the extreme left, policies to bring peace. We should start with the proposals of President Lopez Portillo of Mexico.