VIENNA — WILL 1991 see the collapse of the house that Tito built for Yugoslavia? One disgruntled tenant has just backed off the prospect of demolition. But it still looks possible. Threats to the multinational state appeared soon after its founder, Josip Broz Tito, died in 1980. With him passed the unique authority that kept a ``common home'' together, despite often quarrelsome tenants.
The collective presidency that succeeded Tito never had his authority. On the contrary, it mirrored increasingly jealous rivalries, which Tito had restrained for 35 years of stability.
Ethnic Albanian unrest in Kosovo in 1981 was only the forerunner of naked conflict between major republics. Now, divisions threaten the country as a whole.
On one side is Serbia, the largest republic. It not only wants the once-autonomous province of Kosovo under its thumb; it also hankers for a traditional Serbian dominance to which it claims its size and medieval history entitle it.
Other Yugoslav republics resist this - principally Slovenia and Croatia, the most Western and economically advanced.
Serbia might have ``managed'' rebellious Kosovo indefinitely. But the defeat of the Communists in almost all of last year's regional multiparty elections ensured a Yugoslav problem of acute crisis dimensions. Only in Serbia did the Communists - under an extreme nationalistic, populist leadership - survive. It wants to keep Yugoslavia as it is, within a centralized federation in which an enlarged Serbia is top dog.
Slovenia and Croatia, with new center-right (and nationalist) governments, want a loose confederation of independent, sovereign states, with the right of secession.
The federal authorities in Belgrade are as desperate to prevent unilateral dismemberment of the established state as Mikhail Gorbachev is to prevent similar steps in the Soviet Union.
Confrontation, even civil war, loomed as 1990 ended. Slovenia and Croatia mobilized paramilitary forces to defend their ``independence'' against any challenge from the federal Army, run mainly by Serbs. Croatia lowered the tension by obeying the presidency's call to disband these republican ``private armies.'' But it kept the weapons. Its political rift with Serbia remains.
But Slovenia is so resolved to ``go it alone'' it plans to mint its currency and make legal changes for a new state. Its leaders seem over-optimistic. With but a tenth of Yugoslavia's population, Slovenia does indeed generate a third of the country's gross national product. It tops the hard-currency export account. But Western economists, along with some Slovenes, ask: Is this enough?
EFFICIENT as it may be, Slovenia - like Croatia and Serbia - will still need the Yugoslav and the East European market. It is far from being sufficiently competitive in neighboring Austria and Italy, let alone in world markets at large.
Western support was promised for a realistic federal reform package - which Slovenia opposes. But such support for Slovenia is unlikely. The United States and the European Community have already indicated preference for a united Yugoslavia.
Ironically, the answer to all this lies less perhaps between these saber-rattling arch-rival republics than with what is happening in Kosovo. Not long ago, only an extremist fringe there regarded Albania as an answer to its wrongs. The majority knew they were Yugoslavia's poor but were still better off than those in Albania.
Now, however, Albania's economic and social reform not only fuels Kosovo's demand for home rule. It is also - together with Serbian repression - turning more Kosovar thinking toward uniting with a new kind of neighbor.
One hopes this possibility would deter Serbia's intransigence over Kosovo. It might also help persuade Serbs that only a reformed, decentralized confederation can prevent a Yugoslav breakup, which would be disastrous for all.