No matter what form it has taken—land of the tsars, nucleus of the Union of Soviet Socialist Republics, or today’s All-Russian Federation—the place known as Russia has displayed an enduring capacity to spawn dissidents and an equally striking inability to tolerate them. This is not unusual for authoritarian systems, but in Russia’s case what stands out is the persistence of the phenomenon across centuries and widely varying types of rule, as if “loyal opposition” were a foreign substance rejected by generation after generation of the host organism. “We are a nation of optimists,” Zhores Alferov, a 2000 Nobel laureate in physics, once joked, “because the pessimists have all left.” Since the full-scale invasion of Ukraine on February 24, 2022, nearly a million people, mostly young and well educated, have fled Vladimir Putin’s Russia.…