Some object morally to the war, some politically, others have already completed tours of duty and were revolted by their experiences as an occupying army.
US military deserters have many reasons to refuse to deploy to Iraq and Afghanistan. They are joining a growing army of soldiers who prefer to go to jail or face exile rather than fight in a war they oppose.
About 20 US war resisters have applied for refugee status in Canada. But seeking refuge in a country that is itself getting sucked into the quagmire that is Afghanistan - there are 2,300 Canadian troops already there - is becoming increasingly difficult.
Canadian authorities have already rejected requests for asylum.
Despite this, for 23 year old Tim Richard the route to Canada was still the best option and a risk worth taking.
Tim comes from the mid-western state of Iowa and joined the Army National Guard when he was 17. He served six years as a part time soldier, and his period of service was coming to an end in November 2005.
He opposed the invasion of Iraq but, like many other part time soldiers, he became a victim of a process known as stop-loss, a presidential order brought in during the first Gulf War of 1990-1.
The rule was designed to beef up the number of available troops by extending the period during which reservists can be called up. More than 10,000 soldiers are currently covered by the law. Reservists make up around 40 percent of troops in Iraq.
For Tim Richard, stop-loss meant extending the period he could be sent to war past 2005, when his term of service was due to end, to 2031 - a life sentence for someone who joined out of high school expecting to be called on in national emergencies, such as fighting forest fires or floods.
In October 2005, he got the call he dreaded. A letter landed on his doorstep informing him that he was obliged to serve for 608 days. His National Guard unit was ordered to Camp Shelby in Mississippi for special training before being shipped out to Iraq.
“I was morally against the war,” he told Socialist Worker from his refuge in Canada. “So I decided to go my superiors and explain why I did not want to go, and why I considered the invasion of Iraq to be immoral.”
He inquired about applying for conscientious objector (CO) status, but found that he did not qualify as he was not opposed to all wars, just to the occupation of Iraq. “I was informed that even if I did apply for CO it would take 18 months to be processed, and by then I would have been shipped out,” he said.
It is estimated that up to 15,000 US soldiers have gone absent without leave (AWOL) since the invasion of Iraq and Afghanistan. Around 400 of them have fled to Canada, following the route taken by soldiers opposed to the Vietnam War a generation earlier.
Tim discovered there were others in his unit who were unhappy about the war, but going AWOL was a taboo subject that was never discussed.
“It was during a ‘cultural sensitivity programme’ that I began to have serious doubts about participating in the war on any level,” he said. “There we were learning how to be ‘culturally sensitive’ when searching an Iraqi’s house, and I’m thinking, ‘These guys have every right to resist us, because they’re defending their families and their country’.”
The reality of being part of an occupying army sunk in during one training programme:
“They put us through this exercise where we had to search a mock Iraqi village. They hired around 75 Arabic speakers to act as villagers. During the exercise I opened fire on two of the villagers. If the situation had been real I would have killed them.
“I began to fear what would happen to me if I was in Iraq. How could I live with the thought that I could just open fire like that?
“That night I decided the best thing to do was to break out of the camp and get out of the country. But I was beset by guilt and doubts about abandoning my friends - guys who were also unhappy about the war. I also felt guilty about leaving the military, which for the past six years I had proudly served in.
“My only options were to go to Iraq and take part in an immoral war, or to go on the run and risk jail. But in the end I resolved that to desert was the best thing I could do. At the end of the day this option was also available to other soldiers.”
Escape was not easy. The soldiers were constantly monitored and always carried their weapons. “Camp Shelby was like a prison, and because we always had to carry our rifles, I realised that I could not just dump it and run - that would be irresponsible.
“I resolved to flee at the first available opportunity and even talked to some of my friends to see if they would join me, as they too were opposed to the war. But I was alone.”
Tim’s opportunity came on the eve of deployment.
“We were given an afternoon off to go a Wal-Mart store in town to pick up some personal items before shipping out,” he said. “We were allowed to wear civilian clothes, so the chance I was waiting for had finally come round.
“I slipped away from the main group and hailed a cab to the New Orleans airport. I was very paranoid. I phoned my mother and told her to withdraw all my money from my bank, then I destroyed all my military identification.
“I ripped up my military ID and dumped the pieces in different trash cans, then I did the same to my dogtags.
“I booked a flight to Seattle and then rented a car to get across the Canadian border. Despite my fears, the border guards waved me through. When in Canada I contacted the War Resister Support Campaign, which stepped up to help me.”
Tim Richard, whose father is Canadian, can apply for citizenship but opposing the war means he can never return to his home.
“But other resisters face a tough time, as they can expect to be deported back and dumped in military jail,” he said. “In the US, desertion in a time of war still carries a maximum sentence of death. That is a gamble no one should have to take.”
Despite this, some of those refusing to fight have remained in the US. Carl Webb is a 40 year old member of the Texas Army National Guard and an army veteran.
He had a few months left of his service when he was called up for duty in August 2004 under the stop-loss programme. He refused to be mobilised and has openly defied the army by touring the US agitating against the war.
In August 2005 Webb faced another tragedy when he lost his family home in Hurricane Katrina.
Katrina confirmed everything Carl Webb felt was wrong with the invasion of Iraq and the priorities of the Bush administration.
He told Socialist Worker, “We heard that while the Louisiana National Guard were stuck in Iraq, military recruiters were descending on the shelters trying to sign up people made homeless by the hurricane.
“I went down to look for my folks - whom I eventually found alive and well - but I was also hoping I would be arrested doing what the National Guard should have being doing if they weren’t in Iraq - helping the victims of Katrina.”
Classified as a deserter, Carl Webb is still waiting for the knock on his door. “I don’t want to have to face a court martial - but I consider it my duty to encourage others in the military who oppose this war to take a stand,” he said.