The Lost Veterans
Sergeant Phil Northcutt has been living with his girlfriend Jennifer and their one-year-old son, Kai, in a single room, raised up on stilts over the back yard of a house in Long Beach, California.
It's little more than a crash pad which belongs to a friend of his.
For the moment though, it's the nearest thing that Phil has had to a place of his own in three years.
Phil was lucky - he came back from serving with the Marine Corps in Iraq in one piece. His experiences of serving with the US military changed him so much that he couldn't go back to his old life.
Advocacy groups estimate that Phil is one of at least 1,500 veterans from the conflicts in Iraq and Afghanistan who sleep rough in America's cities every night. It's a problem that the authorities seem reluctant to admit to.
Official figures show that 150,000 veterans of various military conflicts are living in shelters or on the streets, although many charities working with the homeless say the true number is double that.
The current conflicts are already swelling this vagrant population - as more soldiers reach their point of discharge from the army.
When the process of eventual withdrawal from Iraq and Afghanistan begins, it's likely to put further strain on an overburdened system.
Almost half of these 'lost veterans' have drug abuse problems and over a third have serious psychiatric disorders. Many have been to prison.
In 2006, Phil Northcutt was sent to jail for growing marijuana. The only drug which stopped the recurring nightmares of his time in Iraq. He was imprisoned for 11 months.
When the Marine Corps offered him an 'other than honourable' discharge, meaning the loss of benefits, he took it.
Andrew Purcell spoke to many of those, like Phil, trying to get back on track. He finds out more about their struggles reintegrating into civilian society, and why they feel abandoned by the US military.
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