They Chose China
blip.tv -
In this feature documentary, Oscar-nominated filmmaker Shuibo Wang aims his camera at the astonishing story of 21 American soldiers who opted to stay in China after the Korean War ended in 1954. Back home in the United States, McCarthyism was at its height and many Americans believed these men were brainwashed by Chinese communists. But what really happened? Using never-before-seen footage from the Chinese camps and interviews with former PoWs and their families, 'They Chose China' tells the fascinating stories of these forgotten American dissidents.

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Looks like I'm stuck on the wrong side of the GFW for this one. Check it out if you can, I saw this documentary back in college and really enjoyed it. While it was a big event at the time, it (along with the Korean War) has largely been forgotten in America.
One of the soldiers, Clarence Adams, had his memoir An American Dream: The Life of an African American Soldier and POW Who Spent Twelve Years in Communist China published posthumously and it's the best of the books on the soldiers and the only one still in print.
The first book published right after the soldiers' defection, 21 Stayed: The Story of the American GIs Who Chose Communist China presents the soldiers as either troublemakers or dupes. The second book, another memoir, Turncoat: An American's 12 Years in Communist China was published during the Vietnam War and is largely a combination of apology and excuse.