The government’s decision to charge surviving Boston Marathon bomber Dzhokhar Tsarnaev with the use of a weapon of mass destruction struck many Americans as peculiar. At first glance, the Tsarnaev brothers’ bombs do not seem to match the definition or popular perception of a WMD. For decades, that term has been interpreted as referring to nuclear, chemical and biological weapons, which uniquely possess the ability to kill people in numbers large enough to be considered massive. Two factors, among others, help explain the government’s decision: The charge is seen by prosecutors as relatively easy to level—and prove—compared to other possible […]