Belgrade — A year and a half after the passing of its four-decade-long father figure, Josip Broz Tito, Yugoslavia is both better and worse off than anyone expected. Better, because the feared succession struggle and Soviet subversion haven't transpired, and Serbian-Croation hostility hasn't reached the level it did in the early 1970s. Worse, because the economy is in serious trouble and Albanian nationalism has exploded into violence.
Just how much of a political crisis this adds up to in the absence of that great national unifier, the supranational Croat Tito, is largely in the eye of the beholder.
Certainly Serbs, the largest and the traditionally dominant nationality in this multinational state, reacted to last spring's protests in Kosovo as if they were a mortal danger. Troops and tanks were rushed in to suppress demonstrations for a full Kosovar (ethnic Albanian) republic or even (in the demands of a few extremists) Kosovar secession from Yugoslavia. At least eight demonstrators and one policeman were killed in the clashes.
A purge has followed in the university, school, Communist Party, government, and to some extent industry in the southern Kosovo Autonomous Region, which is a subordinate part of Yugoslavia's Serbian Republic. At the latest count (by the Financial Times) some 190 Kosovars have been given long prison sentences in connection with the protests. Control of Kosovo by federal authorities would require, in the view of some observers, stationing in Kosovo of something like a quarter of the Yugoslav Army.
The Russians, however, preoccupied with Afghanistan and then Poland, did not fish in the troubled Kosovo waters, so far as foreign observers can ascertain. (There have been dark allusions to Soviet meddling by some Yugoslav officials, but they have presented no evidence that convinces foreign residents.) The Albanian government did intervene verbally for all it was worth on behalf of its brothers across the border - but this represented no real threat to Belgrade.
The more immediate threat, or so Slovenes, Croats, and a few Serbian intellectuals believe, is ''great Serbian chauvinism'' in reaction to the protests. Serbian response has ranged from bewilderment at the ingratitude of those Kosovars who have had so much money poured into their region, to indignation over lurid press accounts of persecution of Serbs living in Kosovo.
The actual policy has been a tough one, a curtailing of much of the autonomy Tito had granted the Kosovars in the constitutional decentralization of the 1970 s, and a partial return toward the colonial-style Serbian rule of Kosovo practiced in the 1960s.
Serbian anger at the Kosovar ingrates has also revived some of the old Serbian feelings of superiority toward other nationalities. Ethnic Hungarians in the other autonomous region within the Serbian Republic, Vojvodina, have complained of this. Croats identify it in the harsh prison sentences meted out to several Croat nationalists this fall - for such offenses as having ''mendaciously'' written about the situation of Croats. A number of Slovenes also see Serbian chauvinism in the rather strange trial of Serbian writer Gojko Djogo, which has served to publicize the author's alleged crime of writing poems attacking Tito.
Yugoslavs therefore worry that they might slip into the real nightmare of the post-Tito era: virulent nationalism. So far excesses have been avoided, though. The second-largest nationality (and the most suspicious of the Serbs), the Croats, have not been stirred to any rerun of their early 1970s nationalist wave. And as long as this generations-old rivalry doesn't again boil over, foreign observers think Yugoslavia can cope with the Kosovo restiveness without permanent damage.
Of course, if a power struggle should develop at the top, there could be a temptation for competitors to appeal to nationalist emotions. No such struggle has yet materialized, however. The collective leadership set up by Tito has functioned relatively smoothly.
Yugoslav's committee-style leadership, known as ''the presidency of the presidency,'' rotates among the major nationalities once a year. The portraits of Tito gracing every office and shop - in a display of public adulation that would seem to exceed anything seen in the leader's own lifetime - emphasize the very self-effacement of Tito's successors. And the 1970s constitutional decentralization that reserved considerable powers to the republics provides a brake on the acquisition of too much power by any president.
Just how long such self-effacing collectivity can endure is a matter of speculation. Yugoslav officials say they expect it to continue in perpetuity, but foreign observers are more skeptical. They wouldn't be surprised to see one or two prominent leaders emerge, and possibly as early as at next year's Communist Party Congress.
In the end, though, it may turn out that the most serious issue for the immediate post-Tito era is neither politics nor nationalism, but the economy. Yugoslavia currently faces runaway inflation, overinvestment, and dipping exports to the West. Real take-home pay is falling for the second year in a row, and some economists think it won't rise again until 1985.
A year and a half after Tito, then, Yugoslavia is still something of a question mark.