The Western alliance, led by America, needs to help Macedonia at a moment when Greece is needlessly fueling another Balkan crisis. If that regrettably requires diplomatic, political or economic pressure on Athens, so be it.

Greece closed its border with the landlocked republic—a remnant of Yugoslavia—on Feb. 16, blocking access to the port of Salonika, its main gateway to the outside world.

This move was intended to destabilize Macedonia’s precarious economy.It could topple the government unless Macedonia gives in to Greece’s demands on a number of issues.

To counter rising irritation in Europe, Athens allowed some fuel to enter by rail last week.

Otherwise, the borders remain closed, endangering Macedonia’s ability to ship its most important export, early-season vegetables, to Europe.

But it is in Greece’s interest to foster a prosperous, democratic, multiethnic neighbor to its north, not to work toward its destruction.

The existence of Macedonia, the only multiethnic state in the Balkans that is not war-torn, depends on its ability to satisfy its nationalities: a sizable Albanian minority, Turks, Vlachs, Serbs, Gypsies and others.

But the three-party coalition, which includes Macedonians and minority Albanians, faces strong opposition from nationalist extremists in both groups.

Macedonian extremists want the Albanians to have limited power; radical Albanians want parts of Macedonia joined with Albania. If extremists gain the upper hand, Macedonia may not survive as an independent country. A conflict could draw in all the neighboring countries—Yugoslavia, Albania, Greece, Turkey and Bulgaria.

Nationalist passions are running high in Greece. The last government was defeated mainly on the issue. The Greeks fear that implicit in the republic’s name and Constitution is a claim on the Greek province of Macedonia.

The name Macedonia arouses powerful memories that go back partly to the communist insurrection in Greece after World War II, sustained by Tito’s Yugoslavia.

More potently, they go back to the turbulent period after World War I, when many Slavic Macedonians inhabited Greek Macedonia—a period when Greece asserted the principle that all the inhabitants of Greece were Greek.

Large-scale population transfers took place. The injuries suffered Slavic Macedonians, who today form the majority in the republic, gave rise to an irredentist Macedonian nationalism, which in turn inflames Greek nationalism. This irredentism is propagated by Macedonian extremists, not the government.

Greece wants Macedonia to recognize the present borders (it has done so), to delete the references in its constitution to protection of Macedonians outside the country and to remove from its flag the star of Vergina, an old Greek emblem.

Macedonian government could muster only after a shift in diplomacy by the United States. The Clinton administration has not formally recognized Macedonia and established diplomatic relations.

It should do so right away, and it should deliver an economic and humanitarian package and press our allies to do so.

This could persuade Athens that its anti-Macedonian policy will fail, but if Athens does not to come its senses, the United States might have to put on heavy pressure.