That's not to say that all the photographs in Casteel's collection highlight damage. They're just as likely to show how people have moved on, or at least adapted to life without the disciplinarian ethos of military life. For many, this transition to being a civilian is as difficult as the war effort itself.

Rather than showing the former soldier, Casteel focuses on another intimate part of their life - their car. By capturing this personal and passive space, it's as unguarded and raw as an area of the brain itself.

In a car, as messy or as organised as it is, the vehicle is literally that, a vehicle more than just a car. It's a wild stallion, a horse able to take people to wherever they want to go. It's a part of the American Dream - even if it's being used to manage a nightmare.

These spaces, ones usually kept for the eyes of their owner, provide a subconscious portrait of a person's mental state. Whilst it doesn't tell a full story - it certainly goes a long way in telling part of it. By capturing this, we see the motivations of the soldier. Their patriotism, their coping mechanisms when patriotism fails or when the calm and order of everyday life doesn't hit the same spot that military life managed to.

Beer and cigarettes are common, not only for the soldier, but as part of an American way of life. There's a certain machismo involved that is part performance, part entrenched outlook. These seats are as much an unknown man's as one we all sort of recognise from films like Dirty Harry and Bullitt. They're parts of lives we all know, despite not knowing them at all.

American Interiors is the pointed title of the series that was built as an exploratory body of work by Casteel whilst working with veterans over a period of five years. For the photographer, interior is often used as a word for our homes. It's something curated, not just for ourselves to dwell, but for others to see. In the back and passenger seats of cars, Casteel uncovered what a house was never able to reveal.

What we see are seats littered with objects. There's money, guns, root beer and burgers. Symbols of capitalist America itself. But there's also Bibles, biographies and syringes for painkillers - signs of people looking to better their lives or improve a situation, both in the short and long term.

Of his powerful series, Casteel notes, "_American Interiors_ is my attempt to bridge a deep sense of rebellion and outrage towards institutionalised violence (via warfare and the American military industrial complex) with the empathy and sadness I hold for the people who have survived the military experience."

The scars of war are permanent and wide. The psychological damage and trauma is often palpable when one is in the presence of those afflicted. Their intensity of life, perhaps provoked by their relationship with death and suffering, have a corrosive effect on the individual psyche. When this happens en masse, a collective psyche develops. A counterculture of pain. This is part of modern American life, as well as many other countries the world over. In this series, we discover that it doesn't take a face or a name to highlight this, but something far more personal.