Washington sends out mixed signals on Latin American policy

Mixed signals are coming out of Washington these days as the Reagan administration gropes to draft its Latin American policy. Uncertainty is most evident in approaches and attitudes toward El Salvador, Argentina, and Guatemala.

In El Salvador, the Reagan administration leaned heavily on the government of Jose Napoleon Duarte to arrest and bring to trial six National Guardsmen thought responsible for the deaths of four US Roman Catholic women missionaries last December. The United States warned the Salvadorans that continued military and economic aid was at stake. Now the six guardsmen are under arrest.

(Former US Ambassador Robert E. White, fired by the Reagan administration in January, said last week that the delay in arresting the guardsmen was a "big charade," for the Duarte government knew all along the killers were guardsmen.)

But in Argentina, there has been no such human-rights pressuring from the US despite signs that the government of Gen. Roberto Eduardo Viola is embarked on a major crackdown on dissidents. In the face of these fresh violations, the US is pushing for an early resumption of military aid to Argentina -- and the House Foreign Affairs Committee last week voted to lift the three-year-old ban on such aid.

And in Guatemala, the US is studying a similar resumption of military aid against an array of alleged human-rights violations. This week, Gen. Vernon A. Walters, former deputy director of the Central Intelligence Agency and a close confidant of Secretary of State Alexander M. Haig Jr., will go to Guatemala to discuss conditions for the aid resumption.

It is understood that General Walters will tell the government of Gen. Romeo Lucas Garcia that resumption in part depends on an improving rights climate. But Washington, in light of the virtual civil war in neighboring El Salvador, also wants to strengthen the Guatemalan military's ability to "defend [itself] against the guerrillas" active in many parts of Guatemala.

The Reagan administration has also had difficulty steering its Latin American course because it has been buffeted by opposing special interest groups:

* Conservatives led by Sen. Jesse Helms (R) of North Carolina who argue that Cuba and Marxism are the biggest threats facing the US in Latin America.

* Liberal holdovers from the Carter administration who say human-rights violations are bigger threats, downplaying the Cuba issue.

This debate, reaching a crescendo at the time of the assassination attempt on President Reagan, left vacant the post of assistant secretary of state for inter-American affairs until Thomas O. Enders was appointed at the end of April.

Mr. Enders, with no Latin American experience, was staunchly opposed by Senator Helms, but he is General Haig's choice for the job. He occupied the assistant secretary's office for a month before his formal appointment, working on a cohesive Latin American policy.

The pol icy has yet to be disclosed.