It is a debate unlike any seen in modern presidential history: the question of whether a decorated war veteran is a hero. The argument has been prompted by a new book that John Kerry's (searchcampaign dismisses as a political smear but that has nevertheless caught the public's eye.

"Unfit for Command," co-authored by John E. O'Neill (search), a Vietnam veteran who served alongside Kerry, has attracted a huge following, hitting number one on the bestseller lists on Amazon.com and BarnesandNoble.com.

The book questions Kerry's heroism in battle, his judgment as a swift-boat commander and whether he deserved the three Purple Hearts (search), a Bronze Star and a Silver Star awarded to him.

The book has forced the Kerry campaign to admit errors in statements Kerry made in 1979 and 1986 about his vivid memories of heading into Cambodia with his swift boat.

Kerry supporters say the book is "based on lies and distortion." The national director of Veterans for Kerry (searchargues his mistake about a date would have been an easy one to make.

"It's a very watery area. There's no sign that says 'Welcome to Cambodia,'" said John Hurley. "I think the experiences are seared into his memory. I think that he knows that he was under fire in Cambodia. I think the date is what is inaccurate. That it was just not Christmas Eve day." 

Click in the video box near the top of this story to watch a report by Fox News' Major Garrett.