The November 2009 shooting at Fort Hood, the most populous US military installation in the world, was quite scary as a single gunman killed 13 people and wounded 29 others. The sole suspect Nidal Malik Hasan, a US Army major serving as a psychiatrist, has been charged with 13 counts of premeditated murder and 32 counts of attempted murder. Hasan is an American-born Muslim of Palestinian descent.

Subsequently, the Pentagon issued a report recommending that there be better screening of military personnel for signs that they may become violent. The report said, there’s no requirement to screen soldiers for violent tendencies prior to their deployment, and post-deployment screenings rely primarily on soldiers to report their own symptoms on questionnaires. Maj. Nidal Hasan, who’s accused in the Fort Hood shootings, was about to be deployed to Afghanistan when he allegedly opened fire on his fellow soldiers.