“Welcome to the GREAT place,” reads the sign outside the main entrance of Fort Hood, Texas, set in rolling lawns just off US Route 190 — otherwise known as the Ronald Reagan Memorial Highway.

It certainly looks like a pleasant spot to live. In fact, it is hard to believe this 340 square mile, self-contained city of 70,000 people, which resembles a vast, sleepy university campus, is actually the world’s largest military facility. Even the base’s own newspaper, The Fort Hood Sentinel, seems as though it belongs to some idyllic, picket-fenced small town, with its lead stories about pet adoption fairs, children’s pumpkin patches, and Make-a-Difference Days.

There is a certain open-mindedness to Fort Hood as well, as evidenced by the closed-circuit television footage of Major Nidal Malik Hasan, in Muslim dress, buying his morning coffee on Thursday about an hour before he allegedly opened fire on his fellow soldiers.

Although Major Hasan looked a lot like the people that US soldiers are trained to kill in Afghanistan, no one gave him a second glance. And when a shop employee smiled at him, he beamed back.

It has since emerged that Major Hasan was anti-war. But that’s also not unheard of at Fort Hood, which tolerates all kinds of world views (as long as the holders of those views are ready and willing to fight).

In the nearby town of Killeen, soldiers who openly disagree with the wars in Afghanistan and Iraq often gather at a coffee house named Under the Hood.

The organisation Iraq Veterans Against the War holds its official meetings there — it has 1,700 members and 61 chapters around the world. There are a few giveaways that Fort Hood isn’t as serene as its beautifully maintained landscaping would suggest. Take the street names, for example: Tank Destroyer Boulevard, Battalion Avenue, Engineer Drive.

Then there are the hospitals — far more than a population of 70,000 would normally require — and the billboards urging the troops to put their faith in the Creator. “It’s all about HIM,” reads one. Such divine reassurance is no doubt in great demand. After all, Ford Hood is not just a military base; it is a departure lounge — a gateway to another dimension through which tens of thousands of high-school-age Americans are routinely transported from one of the richest, safest countries on Earth to the death zones of Afghanistan and Iraq.

Many return in flag-draped coffins, as the headstones at the nearby Texas State Veterans Cemetery so poignantly demonstrate.

But there is no way of measuring the mental toll on those who come back alive.

When The Times visited Fort Hood in 2007 — back then the names of 685 men and women lost in the wars in Iraq and Afghanistan had already been recorded on memorials in the parade grounds — the chaplain of the 1st Cavalry Division spoke of the “emotional carnage” often suffered by veterans.

Broken marriages, suicides, desertions— all were a fact of life for America’s war fighters, he said (some soldiers return from the battlefield to find out that their stressed-out spouses have cheated on them).

It is estimated that up to a third of all soldiers returning from the front lines have psychological problems, with army doctors frequently treating young men and women with severe post-traumatic stress disorder. This is what Major Hasan, a psychiatrist for the past eight years, did for a living.

The commanders at Fort Hood are all too aware of these problems, and have established many support networks, including emergency hotlines and “stress workshops”, in an effort to avoid the kind of incident that happened on Thursday.

Those at the base are also issued with the 126-page Soldier/Family Deployment Survival Handbook. Clearly these measures are not working well enough. But life at the base goes on and despite the news crews, the surreal veneer of normality remains.

As you leave and head back out into the real world, a digital sign warns you of the risk you are taking. “Traffic fatalities this year are 022,” it says. “DRIVE SAFE.”

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