THE RECENT stabbing of a Russian Jewish leader inside the Choral Synagogue, just blocks from the Kremlin, represents an escalation of the antisemitic attacks that have proceeded in Russia at a low but disturbing level through most of this decade. In Moscow alone, there have been at least seven cases of arson and bombing attacks at synagogues and other Jewish sites, and cemeteries and synagogues have been targets outside the capital too. This time, a 20-year-old man, reportedly tattooed with a swastika, entered the synagogue and repeatedly stabbed Leopold Kaimovsky, 52, director of the Jewish Cultural Center. The assailant from his jail cell described his attack as a "political act" against the "evil" of Judaism.

Americans know only too well how difficult it is for any society to free itself of racism and racist violence. Russia, in the midst of wrenching economic and social change, can offer more plausible explanations than many other countries for why such poisons might spread. But a measure of any society is the vigor with which it fights against such hatred. In this regard, Russia's performance is mixed at best.

Antisemitism is an old scourge in Russia, and its prevalence or absence at any given time is as good an indicator as any of the general health and openness of the country. President Boris Yeltsin for the most part has seemed to understand this, and throughout most of his time in office has spoken out for tolerance and against prejudice. Many Jews have prospered in the new Russia, and Jewish culture and religion have resurfaced after decades of repression.

But other political leaders are open in their antisemitism, and no one in the establishment has been firm enough in condemning them. Extremist leaders, such as Alexander Barkashov and Communist legislator Albert Makashov, attack Jews openly and venomously, and more mainstream leaders cannot summon the political will to disown them. Far from condemning party members such as Mr. Makashov, Communist leader Gennady Zyuganov -- a once and future presidential candidate -- himself speaks darkly of Zionist plots and implicitly blames Jews for Russia's economic troubles.

Jewish emigration to Israel, which had slowed in the past few years, has picked up again, in response both to rising antisemitism and new economic troubles -- two phenomena that are themselves partly related. That Jews can leave should be welcomed. But many Jews in Russia want to stay, to make a life that is both Russian and Jewish. Whether they can do so will be an important sign of the overall viability of Russia's democratic experiment.