Central America peace plan to test Costa Rican leader. Arias plan stresses diplomatic initiatives

Costa Rican President Oscar Arias S'anchez is a diplomatic tightrope walker. Mr. Arias's year-old balancing act between the United States and Nicaragua is due to be put to the test later this month, when he offers his Central American peace plan for discussion at a summit of regional leaders. By holding to his stance so far, the President has earned respect as an honest broker.

Arias's peace plan has won unanimous support from the US Senate, and expressions of goodwill from the White House, but his proposals clearly fall short of the goals President Reagan has set for his policy on Nicaragua.

In large part, say diplomatic analysts in Central America, this is because the Costa Rican President appears convinced that US support for the Nicaraguan contra rebels is a dead end, offering no real prospect of a solution to the regional crisis.

Arias's stress on diplomatic, rather than military initiatives, derives from Costa Rica's declared neutrality in Central America's conflicts. And Arias has illustrated that neutrality by taking a number of actions that hampered the US-backed contra cause.

Most strikingly, Arias closed down an airstrip in northern Costa Rica that the semiofficial, semiprivate US support network built for the contras in 1985. His predecessor, Luis Alberto Monge, though declaring Costa Rica's ``perpetual neutrality'' in 1983, had turned a blind eye to the landing strip's construction. Within weeks of taking office last May, and in the face of fierce protests from then US Ambassador Lewis Tambs, Arias ordered it shut.

Arias has also kept his promise to arrest contra guerrillas caught in Costa Rican territory, thus hindering Nicaraguan rebel efforts to build a ``southern front'' in their war against the Sandinistas. And he has warned contra civilian leaders that, should they take charge of rebel military operations, he will forbid them to meet in Costa Rica.

Adolfo Calero, leader of the largest contra army, has long been persona non grata in Costa Rica.

Such behaviour is in marked contrast to the active support that Honduras and El Salvador, Nicaragua's other neighbors, have offered to the contras' military efforts. And even more surprisingly, Arias has held firm despite his economy's critical dependence on US aid: Costa Rica receives more US economic assistance per capita than any other country in the world except Israel.

Arias has not fallen from his tightrope for several reasons, but key to them all is Costa Rica's 40-year tradition of peaceful democratic rule, unique in Latin America.

That history of uneventful swings between Arias's Social Democratic Party and its moderately conservative rival has given Costa Rica a credibility in international affairs that no other country in the region can match. At home, Arias's peace plan enjoys the opposition's full support, giving it a strength it might not otherwise possess.

At the same time, the President is freed of any unwelcome pressure from the Army, such as his counterparts in El Salvador and Honduras have to deal with, because Costa Rica disbanded its army in 1949.

Costa Rica's reputation of neutrality has won it widespread support in Latin America and Western Europe. Countries in those two regions which share doubts about the wisdom of US Central American policy, and about the Sandinistas' real intentions, find in Costa Rica an ideal regional spokesman. Arias is in fact just winding up a three-week tour of Western Europe, garnering political backing for his peace plan.

Costa Rica's promise of an alternative has also found supporters in the US, as the Democratic Party casts about for a Central American policy. It was no coincidence that as Arias first unveiled his peace plan last February, sitting in the audience was Senator Christopher Dodd (D) of Connecticut, a leading figure in the Democrats' Central America policy debate.

Among Arias's advantages in playing this role are his unimpeachable anticommunist credentials.