Two weeks before his second deployment to Iraq last September, Army Specialist Michael DeVlieger broke down.
"At first, I thought it was something that everybody experienced," DeVlieger told ABC's Bob Woodruff, "and just through time and perseverance I guess it would pass." It didn't pass.
After an 11-day hospitalization, DeVlieger was given a diagnosis of major depressive disorder, three psychiatric prescriptions -- and deployment orders.
"Eighteen hours after he got out of the hospital, he deployed to Iraq," DeVlieger's wife, Christine DeVlieger, recalled. He left for Iraq despite Pentagon policy requiring that service members establish three months of "stability without significant symptoms" before deploying.
"I was a ticking time bomb," Michael DeVlieger said.
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Citing privacy, officials at DeVlieger's base in Fort Campbell, Ky., declined to comment except to say there was a combat stress unit assigned to DeVlieger's base in Iraq.
More than 600,000 Americans have served multiple tours in Iraq and Afghanistan.
"Psychological trauma is cumulative," explained Dr. Paul Ragan, a former Navy psychiatrist who is an associate professor of psychiatry at Vanderbilt University. More deployments can mean more mental stress, and for some, more mental illnesses, he said.
Army surveys show that for those soldiers deployed once, the rate of anxiety, depression and post-traumatic stress disorder is 12 percent. For those deployed three or more times, the rate is 27 percent.
"People who have psychiatric symptoms, actively symptomatic with PTSD or depression, are being sent back to the very situation that caused their PTSD and depression," Ragan said.
The Army's chief psychiatrist, Dr. Elspeth Ritchie, agrees with the Rand Corp.'s estimate that 300,000 service members have demonstrated post-traumatic stress disorder symptoms. Some are returning to the battlefront, although the Army is not keeping track of how many.
"I certainly would not want to lump all soldiers who have experienced post-traumatic stress disorder and say they are impaired and not able to do their job," Ritchie told Woodruff. "I think that would be very stigmatizing."
Many soldiers, as Ritchie points out, receive treatment and cope successfully with PTSD or depression.
"We have a number of reasons for sending the soldiers back to war -- we have a mission, clearly," Ritchie said.
The mission asks a lot of a few. Less than 1 percent of the population serves, and serves again.
"We know the Army is stretched too thin. We know how busy we are. We know we need more forces," Ritchie said.
While Ritchie said she was unfamiliar with the details of DeVlieger's case, she added that if it were true, it "clearly violates our policy." Ritchie said the Army works hard to screen veterans, but there will always be some missed cases.
The military is increasingly medicating its warriors, and in some cases, returning them to the fight.
Ritchie defended the concept. "You have to remember, PTSD is a treatable disorder, and you can have symptoms and still do your job quite well."
Twelve percent of soldiers in Iraq and 17 percent of those in Afghanistan reported taking antidepressants, anxiety medications or sleep medications in the Army's most recent mental health survey.