First the House rejected military aid for the Nicaraguan contras -- that was good, a blow against a misguided intervention. It went on to approve a Democratic alternative to aid refugees and facilitate peacemaking -- not so good: it put no muscle behind the call to negotiate. Then, having meanwhile rejected a Senate-approved and administration-accepted plan for non-military aid to the contras, the House threw out that same Democratic alternative, 303-123. Democrats wished to derail any legislative vehicle the president might later try to commandeer; Republicans were mad at the Democrats. Thus did Congress kill the administration's policy and offer no substitute: our new Nicaragua unpolicy.

What now? Under the congressional heavings, a workable policy may be struggling to be born. Let us hope so. Congress opposes military intervention, proxy or direct. On this issue there is a real gap, but President Reagan has no wise choice now except to rule out intervention. But there is only marginal congressional favor for the Sandinistas' internal order and there is much distrust of their pro- Cuban and -Soviet foreign orientation. Congress had rightly bridled at the use of force when means short of force had not been brought to bear against a regime with which the United States is not at war. Surely it is ready to support other means now.

What needs to be done is to organize the non- military means and to establish reasonable ends to apply them to.

The instruments should include a further economic squeeze; its effect could be substantial, since the United States is Nicaragua's No. 1 trading partner. As the prospect of military intervention fades, it should become progressively easier to enlist other Latins in economic sanctions and in political pressures designed to exact a price for the Sandinistas' failure to honor the pledges of pluralism and nonalignment they made to the hemisphere in return for its help in ousting the old dictatorship in 1979. These pressures could include condemnation and diplomatic isolation.

They should be applied first to obtaining a cease- fire -- a merciful mission given that Congress has now cut off the contras' from their basic source of military aid. In conditions of a cease-fire, the Contadora regional peace effort becomes at once more feasible.

The second goal should be to induce the Sandinistas to open up a dialogue with the opposition, as the Salvadoran government has done even while the Salvadoran insurgents are still fighting. Contadora has a direct relevance here too. American-Nicaraguan negotiations can be used to promote a dialogue of Nicaraguans and to advance the Contadora talks.

The Reagan administration is stung by the defeat of its military option in Congress. But a new American consensus is there waiting to be formed, if it will take a hand.