Perhaps no one could have anticipated that the stresses of his job as an Army psychiatrist counseling traumatized veterans of Iraq and Afghanistan, coupled with his own conflicted feelings about Islamic terrorism and dread of being deployed to a war zone, would result in Maj. Nidal Hasan standing accused of killing 13 and wounding 38 of his fellow soldiers at Fort Hood Army base in Texas last week. The factors that cause certain men and women to snap under pressure are as unpredictable as they are devastating to the individuals involved and those around them. But in hindsight, it is clear the Army ignored multiple signs that something was amiss.

Over the weekend, National Public Radio reported that Dr. Hasan was put on probation at the Uniformed Services University of the Health Sciences in Bethesda, where he earned a medical degree, and that he was later disciplined for proselytizing about his Muslim faith with patients and colleagues.

Later, at Walter Reed Army Medical Center in Washington, where Dr. Hasan served before being sent to Fort Hood, his co-workers reportedly tried several times tried to warn superiors his loyalty might be in question after he praised suicide bombers.