Nidal Hasan was at the heart of one of the most dangerous terror groups on the Arabian Peninsula . `` I move freely in Yemen , '' he said in March 2010 . Growing up and living in U.S. gave him a unique understanding of U.S. society . He mocked U.S. intelligence for not picking up his e-mail traffic with Maj. Al-Awlaki . He had escaped one previous attempts to kill him .
Nidal Hasan was at the heart of one of the most dangerous terror groups on the Arabian Peninsula . Growing up and living in U.S. gave him a unique understanding of U.S. society . He mocked U.S. intelligence for not picking up his e-mail traffic with Maj. Al-Awlaki . He had escaped one previous attempts to kill him .