One in five US soldiers who served in Iraq are suffering from post traumatic stress disorder. Channel 4 News gained exclusive access to the major American military base at Fort Hood.

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Their President always said he would bring them home. But no one planned for the scale of the problems American soldiers returning from Iraq might bring with them. Current figures suggest more than 20 per cent are reporting with mental health problems - the figure increases with every additional deployment.

And America's decade long "war on terror" has been deployment heavy, with little time at home in between.

That experience is translating into some worrying figures at America's largest military base, Fort Hood, in Texas - home to 60,000 troops, one tenth of the US army. Channel 4 News was given exclusive access to the base, to look at their new arrangements for dealing with soldiers bearing the psychological and physical scars of war.

In the past six months at Fort Hood, soldiers have had 10,000 counselling sessions. Some 6,000 servicemen and women there are on anti-depressants, 1,400 on anti-psychotics.

It is a battle on the home front the US military never planned for. And it is scrambled to come up with the right kind of help for those soldiers who so desperately need it. There are now 36 of these so called "Warrior Transition Units" on bases across the US, currently caring for 9,000 soldiers.

The army says there are centres of excellence, designed to offer appropriate care within a military structure, to soldiers with complex, serious, physical and mental health problems. But the units have also been called warehouses for despair, where soldiers are overmedicated, and roughly treated. Channel Four News spent two days in the Fort Hood unit.

Wounded Warriors: US Army face mental health crisis (Getty)

First Sergeant Orlando Garcia is a big guy. Not the kind of guy you would want to make too angry. Dressed in his fatigues, with a classic US Army buzz cut, he looks your model infantryman.

But it is when he begins to cry, full tears sliding down his cheeks, that you get a glimpse of what the legacy of fighting in Iraq feels like.

He lost six of his men, on patrol in Iraq, he says. A targeted explosion, and then another. He rolls up his sleeve, and shows me the tattoo he has just had done, of their initials wrapped inside an American flag.

The trauma manifested itself in strange ways, he recalls. His short term memory disappeared, he would cry incredibly easily, at anything, and then one day, he dropped his daughter off at cheer practice, and then completely forgot to pick her up. In fact, completely forgot he had even taken her there.

He says the hardest part was admitting there was something wrong with him...

"My job is, you know, top gun. Get them roughed up. Deal with it. Move on, you know, infantry. Get out there, got to finish the fight. And it wasn’t until it really started happening to me, that these things started happening to my short term memory, and I needed help."

Inside the Warrior Transition Brigade at Fort Hood, he says he has found the right kind of help, although he is still recovering, after two years. Sergeant Garcia says, "You’ve got to work at it. I took everything that they had, the different programmes, breathing techniques. I’d do massage therapy, um, acupuncture. Some of the stuff didn’t work for me, the stuff that didn’t work for me I just shoved off to the side."

Another soldier, who spoke to us on condition of anonymity, used these terms: "I'm just appalled by the process. I would think that they would have by now a little bit better understanding of what's going on. A little bit better grasp of what the soldiers are going through and the kind of treatment. It's hard to be caring and concerned and then be treated like you're in an infantry line unit at the same time."

It's hard to be caring and concerned and then be treated like you're in an infantry line unit at the same time.

"Care and concern" is the motto of the WTU at Fort Hood. But as one senior officer told me, the military credo of "command and control" applies as well: "The medical folks can't do it without us and vice versa. We need that to make it a workable situation for the soldier," Captain Jose DaCunha said.

When I asked whether someone who was sick needed to be commanded and controlled, he said: "He's still a soldier, and he's in the military, and yes, you need that, that command and control because otherwise the soldier probably wouldn't do the right thing. I mean I totally disagree with having just the medical folks take care of the soldier, because there's certain things that are innate to being a soldier that require structure."

Being treated like a soldier, rather than a patient, clearly doesn't work for everyone, particularly when the mental health care you need is in short supply on the base. Although there are 60,000 soldiers, there are only 38 psychiatrists in the Resilience and Restoration Centre.

Each month, more than 4,000 soldiers on the base seek psychological help. Not surprising then that an average of nearly 600 soldiers are sent off base to private clinics in the neighbouring town of Killeen.

At one such clinic, Maxine Trent blames multiple deployments - without enough time in between - for the high incidence of severe psychological trauma, hyper vigilance, nightmares and anger.

She says, "the system is overwhelmed. We have intensified and compounded the psychological distresses. We have folks who I don't know how to tell you they vibrate they're so anxious."

Back at the base, bulldozers are shifting earth around the site of a new $50m base, under construction to house the Warrior Transition Unit. A new home for those haunted by what they did and saw in Iraq. Whether they can be made better by the system that sent them there in the first place is unclear, at best.

America's wounded warriors: Master Sergeant Orlando Garcia
Master Sergeant Orlando Garcia was a 1st Sergeant in the 18th Cavalry Division based in Iraq. He entered the Warrior Transition Brigade in July 2008 suffering from intense PTSD and a serious spinal injury.

Sgt Garcia told Channel 4 News he believed his mental health issues began after he lost six of his colleagues to an IED attack in Iraq, and two more very shortly afterwards.

He said he felt huge guilt that he could have done more to save them. On his return to United States, he realised his experiences had affected his memory, and he suffered from depression.

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