Then came the September 11 attacks. Deployed to Iraq for 14 months, the one comfort for Mr Dickenson, who was posted to Nasiriyah, was that his unionised job in a Wisconsin food warehouse was secure.

Then his wife received a letter. The company was bankrupt. His job, his $18 an hour salary, his pension and health insurance were all gone.

“I came back facing mortgage payments, hospital bills, car payments and no job,” he told The Times yesterday.

“I was considering a career in the Guard, but not any more. The Guard is supposed to be a supplemental force, not a battle force. It’s not been used the way it was intended. It is going to lose all its educated people with good jobs, because people can’t afford it.”

Mr Dickenson’s disenchantment and economic plight reflect a growing crisis for America’s National Guard and Reserve units. They are made up of the country’s “citizen soldiers” and now bear an enormous burden.

Long deployments and the risk of death have bred such disenchantment — and a significant drop in recruits — that General James Helmly, the chief of the Army Reserve, recently told the Pentagon that it is “rapidly degenerating into a broken force”.

Most of these soldiers are men and women who have day jobs as electricians, firemen, teachers, local politicians, shopkeepers or doctors. Some of them are simply students looking for financial help with their studies who joined up before the September 11 attacks, attracted by the old sales pitch: give us two weeks a year and a weekend a month, and we will give you cash, job training and the chance to fight fires or help local towns hit by natural disasters.

But Afghanistan and Iraq have changed all that. Because of the massive global commitment of America’s regular military, these part-time soldiers now represent nearly 50 per cent of the 150,000 US troops now in Iraq.

They have suffered 20 per cent of US deaths in Iraq, according to their commanders, or nearly 300 of the 1,480 killed. But it is the massive impact that these long deployments have on their lives back home that is breeding the greatest resentment.

Despite a 1994 law obligating employers to give Guard or Reserve members deployed for less than five years their old job back, it is hard on small business owners and the self-employed, and can be circumvented by companies who claim that they need to “restructure”.

A recent study found that 40 per cent of Guard and Reserves have lost substantial income while overseas. There have also been nearly 5,000 complaints lodged against employers by returning soldiers demanding their old jobs back. Having fought in Iraq, thousands are facing an even tougher battle when they return home: heavy debt, unemployment and broken marriages.

“The biggest problem is predictability,” said Lou Leto, of the Reserve Officer Association. “You’re told you’ll be going for six months. You tell your employer that and then, boom, you’re extended: you don’t come back. Then you come back and six months later you’re deployed again. We’re frequently coming across people who have lost their businesses.

It’s having a big impact on retention.”

They are fighting an uphill battle in rural America, which provides 70 per cent more recruits for the Guard and Reserve than the cities.

Barbara Paige, from Manning, Iowa, has her two sons Mike, 24, and Matthew, 25, in Afghanistan. Like the rest of the town, she is immensely proud of them, but adds: “The burden on Iowa has been huge. I guess I feel the National Guard has always been the one to help with natural disasters.Now a lot of Guard men and women are going on to the front line — and that’s scary.”

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