PRESIDENT BORIS YELTSIN'S second bout of health trouble in four months is a setback for the Balkan peace process. It comes shortly after a show of camaraderie between Mr. Yeltsin and President Clinton heralded "complete agreement" on the need to end the 3 1/2 -year Bosnian civil war. Discord remains on how Russian troops might be used alongside a dominant NATO force in policing a territorial and political settlement, but defense ministers were given orders from the two presidents to work something out.
One of the results of Mr. Yeltsin's illness is cancellation of his planned meeting with the leaders of Serbia, Croatia and Bosnia in Moscow just before they convene for peace negotiations in Dayton, Ohio, next Wednesday.
The timing is particularly unfortunate because of the approach of Russian elections. If Mr. Yeltsin should die or be too infirm to run for another term, his likely replacement would be Prime Minister Viktor S. Chernomyrdin. While Mr. Chernomyrdin is much admired in Washington, there are bound to be doubts whether Russia's political center can hold. The nation's economic situation has stabilized somewhat, but a national sense of frustration could help politicians less friendly to the United States.
If the U.S. and Russia succeed in cooperatively imposing a peace on Bosnia, the symbolism and precedents would be important. Both big powers, with their nuclear duopoly, kept JTC war-prone Europe at peace even as they faced each other across the Iron Curtain. The question now is whether they can shut down the bloodiest European conflict of this half-century through a relationship built more on partnership than hostility.
Proposed NATO expansion eastward is a sore point across the spectrum of Russian politics, arousing as it does ancient fears of encirclement and technological inferiority. It is in that context that the military arrangements for policing a Bosnian peace agreement become so sensitive. Although Mr. Yeltsin has refused to put Russian troops under NATO command, he might be willing to accept the use of a token Russian force -- perhaps 2,000 strong -- for a strictly support, non-combat role. But if illness forces his position to weaken, critics like Gen. Alexander Lebed, a political rival, might demand a larger Russian role in the Balkans.
This danger underscores the importance of bringing peace to Bosnia. Mr. Yeltsin's continued effectiveness would be an asset, but U.S. policy has to depend on more than the good health of an ailing leader. The end goal should be a secure relationship with Russia.