He was by turns caring and contentious, a man quick to say “I am blessed” in casual greeting yet one who seemed to stew in discontent that he could not always keep to himself.

Army psychiatrist Nidal Malik Hasan, suspect in the assault that killed 13 people at Fort Hood, Texas, and hurt 30, salved the emotional wounds of troops returning from war even as he objected to his own looming deployment and argued with fellow soldiers who supported U.S. war policy, say those who know him professionally and personally.