BORIS YELTSIN'S emergency admission to a hospital June 11 rang alarm bells throughout the corridors of power here, as officials wondered once again about their leader's long-term viability as president.
The latest medical reports were reassuring, and a presidential spokesman said the president is continuing to carry out his duties as head of state.
But coming in the wake of a series of questions about the president's health, this latest incident forced analysts to consider the prospects for Russia's stability under a government without Yeltsin. And they were not sanguine.
"Yeltsin is a stabilizing force," says one Western diplomat, speculating that any successor would have less control in holding the balance of power in the Kremlin.
Even the president's political enemies express concern over the country's political future without him.
"In spite of the huge number of negative traits of Yeltsin and of his policies, it is very important for Russia and for democracy here to have normal elections next year, and for everything to be calm until then," says Vitaly Tretyakov, a prominent political commentator and vigorous critic of the president.
Elections to the State Duma, the lower house of parliament, are due in December, and a presidential poll is slated for June 1996.
According to the Constitution, Prime Minister Viktor Chernomyrdin would assume power as acting president in the event of Yeltsin's "sustained inability due to health to discharge his powers." He would then be obliged to call early presidential elections within three months.
"But Russia is not such a banal country that things would necessarily be that smooth," warns Mr. Tretyakov. He recalls that while Yeltsin was hospitalized for a minor operation last December, the war in Chechnya moved into top gear.
The Russian president's chief value now, the Western diplomat suggests, as the country picks its way toward a free-market democracy, is his skill as a ringmaster, keeping competing interest groups more or less in equilibrium.
Refusing to identify himself definitively with any particular political party or economic lobby, Yeltsin has made himself the symbol of Russia's transition away from communism - a role difficult for a successor to assume.
Mr. Chernomyrdin, for example, though he has won wide respect and support for his political savvy and ability to occupy the political middle ground, is nonetheless the head of a new political party, Russia Is Our Home, which is contesting the upcoming Duma elections.
Were he to take over the presidency in unexpected circumstances, the diplomat predicts, rival political groupings - and back-room cliques in the Kremlin - would be "seriously concerned."
"It is no secret that some people surrounding the president are jealous" of Chernomyrdin, government spokesman Sergei Kolesnikov points out.
Such jealousies could easily erupt into ugly power-plays, and even the possibility of an attempted putsch could not be ruled out, according to Tretyakov.
At the very least, the Western diplomat says, power struggles would effectively halt the activity of the authorities for a while, making it "more difficult to do business with the Russians" or to "get decisions out of the government" on either international or domestic matters.
Yeltsin has made himself the symbol of Russia's transition from communism - a role difficult for any successor to assume.