A second critical decision must also be made immediately: How vigorously to require that U.S. intelligence services and law-enforcement agencies focus on the possibility the Tsarnaev brothers are part of, or were materially assisted by, international terrorist groups. Their Chechen homeland has been the source of innumerable terrorist attacks against Russia in the past two decades: bombings of subways and apartment buildings in major cities; the 2002 hostage-taking at a major Moscow theater that left more than 175 dead, including 30 to 40 Chechen terrorists; and the 2004 bloody school hostage-taking in Beslan (in the Russian Caucasus near Chechnya), with nearly 400 dead and 700 injured or wounded, including many young children and all 40 terrorists.

Moscow’s authorities countered Chechen terrorism against Russia through brutal military responses against the hostage seizures, and in Chechnya, Moscow’s tactics themselves are responsible for much loss of innocent life. Obviously, Chechen separatism played no role in the Boston Marathon bombing. Increasingly in recent years, though, those Chechens prone to terrorism, overwhelmingly Sunni Muslims, have turned to radical Islamists for assistance. As Chechen separatists were radicalized, they became part of broader international terrorist activities in places as diverse as Afghanistan, the Middle East and North Africa, completely unrelated to grievances against Russia.