EVEN though it is on the verge of achieving its territorial goals in Bosnia-Herzegovina, the Serbian political and military monolith built by President Slobodan Milosevic has little cause for celebration.
The unity that allowed Mr. Milosevic and his cohorts to pursue the armed partitions of Croatia in 1991 and Bosnia last year is now beset by deep political disputes, unprecedented economic catastrophe, corruption, and personal rivalries.
``There is an impression that the Serbs have won the war, but nobody is happy,'' says Predrag Simic of the Institute of International Affairs here. ``Everybody fears the coming days and months will be the real test for the Serbs.''
A Western diplomat agrees: ``There are definitely deep divisions within the [Serbian] camp.''
The willingness shown by Milosevic and Bosnian Serb leader Radovan Karadzic to compromise in efforts for a Bosnian peace appears in part due to their recognition that their problems will worsen the longer the war persists.
Mediators were hopeful yesterday that Bosnia's warring factions would agree to modifications in the peace plan that would secure Muslim access to the Adriatic Sea - the key sticking point.
The inter-Serb feuds will force Milosevic to employ all his political acumen in maintaining control over the restive pieces of his formative empire.
``The future is absolutely uncertain,'' says Milos Vasic, the deputy editor of Vreme, a liberal Belgrade magazine.
Tensions first began when Mr. Karadzic's leadership spurned Milosevic's call last May to accept the now-defunct Vance-Owen peace plan. That prompted Croatia's Serb rebels to mount their own act of defiance with a June referendum on independence to prevent Milosevic from betraying them in peace talks with Zagreb. Challenge to Karadzic
But the most-dangerous rift in Serb ranks opened Sept. 10, when tanks and troops of elite units of the Bosnian Serb army seized control of the northern Bosnian Serb stronghold of Banja Luka from Karadzic's civil authorities and called for his resignation.
The revolt reflected the abysmal conditions prevailing in much of the Serb-controlled areas of Bosnia, including food, electricity, and fuel shortages; a war-ravaged infrastructure; massive unemployment; widespread poverty; and huge numbers of refugees.
Many analysts say those problems, the prospect of even worse suffering this winter, and Milosevic's growing inability to bail out the Bosnian Serbs because of Serbia's own economic catastrophe augur even greater inter-Serb conflicts.
``The Banja Luka affair is the first serious blow and just a taste of what is going to happen,'' Mr. Vasic says. ``Karadzic said in early 1991 that the Bosnian Serbs can live without bread, but not without a state. They've got what they wanted.''
Many Bosnian Serbs have shifted their affections to Vojislav Seselj, an ultranationalist and suspected war criminal who heads the Serbian Radical Party, the No. 2 party in the rump Yugoslav union of Serbia and Montenegro.
Mr. Seselj is increasingly seen as a threat to Karadzic's Serbian Democratic Party. Not to be outdone, Milosevic's Socialist Party of Serbia (SPS) is now trying to build a base among the Bosnian Serbs. The Banja Luka rebellion ended Sept. 17 with Karadzic agreeing to review the rebels' economic demands. They, in turn, dropped their call for his resignation. But frictions persist.
Milosevic also faces serious problems with Croatia's rebellious Serbs, whose dire economic straits make them dependent on Belgrade for food, fuel, and arms. Many worry Milosevic can no longer support them and is ready to strike a deal with Zagreb in which Serb-controlled areas of Croatia would be granted autonomy but remain within the republic. For that reason, the rebel Serb leadership is split between pro- and anti-Milosevic factions. Trouble at home
Milosevic has failed to arrest the economic crisis that worsened with the fall of Yugoslavia, two years of war, and the May 1992 imposition of UN sanctions against Serbia and Montenegro.
Almost 2,000 percent monthly inflation has rendered the Yugoslav dinar valueless and resulted in bare shelves and rationing of staples. Few enterprises function; millions are unemployed.
Seselj, once Milosevic's loyal follower, is now threatening to call a no-confidence vote in Serbia's minority SPS regime, which rules only with Seselj's support.
Milosevic also is wrestling with Montenegro over food shortages and autonomy. Montenegro has reacted sharply to reports that Milosevic is overseeing the drafting of a new constitution that would abolish its autonomy and concentrate power in a central government dominated by Serbia.
Montenegro has threatened to hold a referendum on secession if Belgrade tries to withdraw its autonomy. That, many analysts worry, could trigger serious turmoil within rump Yugoslavia, as Montenegro is Serbia's only link to the Adriatic Sea.