Had you thought the Reagan administration was indulging an obsession with Cuba, thrashing about somewhat incoherently, pushing weapons here and threats there, gnashing its teeth injudiciously since sooner or later it might feel compelled to do something military and rash in order not to look (by its own lights) silly?

The thought has crossed my mind, but perhaps it is becoming less valid. I have been hearing a few things and trying to put the pieces together, and it appears now that the administration has, let us say, 57 percent of a Cuba policy, not a neat, whole policy but one with some emerging shape and design.

The prime objective--no surprise--is to get Fidel Castro to curtail his foreign adventurism. The interesting thing is the administration's method in going about it.

The last thing on President Reagan's mind, it appears, is American military action. He is not loath to let the Cubans and their partners in Nicaragua and El Salvador worry. But the Pentagon would have to feel that any military action chosen would work reasonably well, and so be seen--that shortens the list. The State Department asks that, on balance, action improve rather than diminish the American position--another list-shortener. One can speculate on what Reagan might do if, but I surmise he is not going off the deep end, yet.

The thrust now is to make it harder for the Cubans in their overseas commitments, and at home, and to do this chiefly by enlisting the self-interest of other nations. The policy has a military aspect but is, in the sense of rallying others, principally diplomatic.

On the Cuba-Nicaragua-El Salvador triangle, the administration is trying to raise hemispheric consciousness of Cuba's and Nicaragua's direct support of the Salvadoran extremist left, and of Nicaragua's internal turn toward the Cuban model. Another "white paper" may be published, if it can be burn-proofed. At key foreign points where the Cuban-Nicaraguan-Salvadoran combination takes sustenance--Mexico, France and Germany, the Socialist International--the administration is pressing politically.

Reagan officials made sure last Sunday's elections came off in Honduras--to show the American commitment to elections planned next March in El Salvador and to help draw the Honduran army more deeply into impeding the flow of military men and materiel across Honduras to El Salvador. By better training, communications and intelligence, it is hoped that the Salvadoran junta will interdict more of that same flow. Meanwhile, the junta is being pushed to clean up its act and to prevent radicals of left and right from torpedoing the March elections.

At a second place where Cuba is exposed, Angola, the administration, with its chief allies and assorted Africans, is advancing a Namibian independence plan linked to an Angolan political process meant to squeeze out the Cubans.

At a third place, Ethiopia, the United States is trying with a whole other cast of characters, African and Arab, to raise the cost of Cuba's engagement.

There is a glint in the administration's eye: suppose some tens of thousands of returning Cuban soldiers were repatriated to the job-short slum that is their homeland, even as the United States shut off the emigration safety valve by which Castro released 70,000 malcontents last year. Does that not heat up the social tinder? Enlarge the prospective audience for "Radio Marti," the new station by which Reagan plans to beam news of Cuba to Cubans?

In brief, a pattern is becoming evident. The administration's approach to Cuba has not all unfolded from a single guiding intelligence, but the pieces are coming into rough fit.

Is it a smart policy?

1)Ronald Reagan has a certain license, if only because Jimmy Carter tried it the other way and failed. We can discuss another day whose fault it was. The fact remains that when Carter took office there was a promise of American-Cuban d,etente and when he left nothing had been resolved and Cuba was foraging widely.

2)Americans are, I think, dubious about using force against Cuba, or in any Caribbean/Central American context. But they agree they don't like Castro. Reagan's policy, moreover, is designed to mesh with the interests of many other nations, most of which would flee from an interventionist line. International company doesn't assure success, but it should help bring the American public along. Nor would it hurt if the administration said out loud what's on its mind.