JOSIP BROZ TITO, who died yesterday at age 87, lived a turbulent 20th-century life. He fought for the Bolsheviks in the Russian revolution of 1917, and 20 years later Stalin set him up as head of Yugoslavia's Communist Party -- seemingly the perfect flunky. Yet in World War II he emerged as the consummate nationalist, leading his country's anti-Hitler forces to victory and at the same time brutally crushing his ethnic and political rivals -- most of his without Soviet aid. Stalin's effort to bring him to heel provoked Yugoslavia's famous break with Moscow in 1948. This is how "Titoism" -- national communism uncontrolled by the Kremlin -- came into being.

At its heart was, and is, an intense, militaristic anti-Soviet nationalism. It meant to lift Yugoslavia above the differences that still make "Balkan" a synonym for ethnic fragmentation and instability, and to prepare the people as well as the army to make an invader pay. But President Tito also realized he had to find a new basis, other than the old methods of force, to sustain Yugoslav independence and his own power. This accounts for the various liberal permutations of Yugoslav communism. Over the years they accomplished their intended effect of attracting the people's loyalty to the idea of a united Yugoslavia, and of making still-socialist Yugoslavia eligible for Western patronage. President Tito also helped invent the "nonaligned" movement -- a bloc that could help keep Yugoslavia independent of the Soviet and American blocs and, not incidentally, a stage on which to strut.

Winning a national and civil war, imposing a revolution, ruling for 36 years while keeping his country united and at peace, hauling Yugoslavia toward modernity, contending with the great powers: by these achievements Josip Broz Tito made himself larger than life and gave his country an outsized international role. But his death makes the question that has long shadowed him and Yugoslavia piercingly real.

Can the system shaped and guided by one patriarchal figure survive his departure? Or will it be loosened, perhaps even dissolved, by ethnic feuds or by Soviet subversion or worse or by a loss of the unifying vision and political shrewdness of the late president? Jimmy Carter, playing catch-up, recently said the right words to assert the American interest in seeing the Yugoslavia remains outside Soviet clutches. Yet the burden of maintaining their national integrity falls first on the Yugoslavs themselves. Much as they hate to concede it, as a nation they are still an experiment. One does not have to doubt their partriotism, courage or intelligence to wonder how they will fare without the founding father.