Most U.S. Attacks Linked To Islamic Extremism Were Carried Out By Citizens

Half of U.S. attacks linked to Islamic extremism since 9/11 were committed by men born in the United States, according to the Times. Even the 9/11 attackers themselves were in the U.S. either on a tourist, student or work visa, suggesting that refugees pose less of a risk to national security than some politicians may think.
http://talkingpointsmemo.com/livewire/us-terror-attacks-citizens