The United States has naturalized at least a few thousand alleged terrorists in recent years. In fact, four of the 13 most notorious terrorism arrests since 2009 involved naturalized U.S. citizens. Five cases involved native-born U.S. citizens, while eight involved foreign nationals (it appears the Boston Marathon bombing included two foreign-born brothers), all of whom had received multiple U.S. immigration benefits. What follows is not a comprehensive list, but it does reflect the most significant U.S.-based terrorist incidents since 2009.