"I was on call every third night for three years," said Ragan, adding that the long hours aren't the worst of it. Talking to soldiers who have Post Traumatic Stress Disorder (PTSD) from combat can be quite chilling.
"The horrors of war of what they told me over the years would curl the hair on a bald man's head," said Ragan, "although you should have the training to deal with this."
Ragan said that psychiatrists are well-trained to deal with such stressors in the military. Moreover, compared with some other situations in which psychiatrists are sent off to war with little notice, Hasan had years of training to prepare for a military setting.
"These things are stressful, but the training should be what gets people to a place to where people can cope with that. He had lots of training. And he was older," said Ragan. "I hate to think what it was like for physicians during WWII and you get three months."
Hasan, 39, got his medical training with the military at the Uniformed Services University of the Health Sciences in Bethesda, Md. He graduated in 2003 with a degree in osteopathy and later finished his residency as a psychiatrist. In 2009, Hasan completed a fellowship in disaster and preventive psychiatry at the Center for Traumatic Stress.
He was promoted to major in May, according to the Army Times.
"This is a guy who's been in a very protected secure environment and people are saying it's time for you to take your training wheels off and go," said Ragan. "I think the die was cast before he even arrived at Fort Hood."
ABC News' Emily Friedman, Brian Ross, Joseph Rhee, Anna Schecter, Avni Patel, Ethan Nelson, Desiree Adib, and Courtney Hutchison contributed to this report.