"Meanwhile, the wait for answers continues. The attack took place in an area saturated with video cameras. Within hours, one television station was showing footage of the killing -- albeit from a considerable distance. Nemtsov was almost certainly under surveillance at the time.

If the Kremlin did not know before, it very likely knows by now who the killer was. Its next decision will be how to use the information for its own purposes. Whether or not the actual perpetrators are caught and punished, all know who created the climate of hatred in which liberal politicians are likened to "jackals who hang around foreign embassies" and a "fifth column" of traitors.

Nemtsov in his later years was never a threat to Putin's regime. Hardly a radical revolutionary, he cooperated with the authorities to avoid violence by moving the site of the first major Moscow demonstration in December 2011, and he participated in discussions with then-President Dmitry Medvedev about reforms of the political system.

Having come to symbolize for most Russians the disorder of the 1990s, he had little chance of rising to the top again. Indeed, he was the kind of liberal -- unbowed, unabashedly pro-Western, unpopular -- whom the Kremlin loved to hate. Now it will have to find somebody else."