He's been portrayed variously as a traitorous turncoat, a misguided kid and an American in the wrong place at the wrong time.
But according to news reports out Monday, Usama bin Laden's Al Qaeda network saw Taliban fighter John Walker Lindh in another, very troubling way: as a perfect terrorist.
The more Pentagon officials learn about "Taliban John" in their field debriefings, the more sinister the confused middle-class 20-year-old from northern California seems, Newsweek magazine reported on its Web site Monday.
Administration officials have learned that Walker, who uses his mother's last name and is being held by U.S. forces on the USS Peleliu, currently cruising in the Arabian Sea, was more than a simple Taliban foot soldier.
Instead, the news magazine reports, Walker was a member of Al Qaeda and trained at its terrorist camps; learned to use explosives and poisons; learned how to avoid attention at airports; and may even have met with Al Qaeda's top brass, including bin Laden himself, a detail Pentagon officials say they are skeptical of.
Besides giving frightening credence to Walker's warnings of a biological attack on the United States in coming days, the allegations of his involvement with Al Qaeda will play a huge part in how he will be treated.
The debate over how to deal with Walker — a United States citizen and yet a soldier fighting on the side of America's enemies — is fierce and, for some, mottled with moral grays.
Walker's free-thinking parents wanted him to experience a variety of cultures and choose his own spiritual path, and with their support, he became a Muslim in his teens after reading The Autobiography of Malcolm X.
But instead of following mainstream Islam, Walker's religious journey, possibly influenced by the fundamentalist Saudi-based Wahhabi movement, took an extremist turn.
After attending religious school in Yemen and doing what he told his parents was relief work in Pakistan, the boy from a comfortable Bay Area suburb crossed the Afghan border in March of this year to become a holy warrior for the Taliban — the harshest Islamic regime in the world, ruling over a land ruined by war and drought.
Now that he's back in American hands, this time as a prisoner of war, it's unclear whether "Taliban John" should be treated a treasonous American, a soldier for a foreign power, or a victim of brainwashing.
President Bush said Monday he has not "decided on what to do with Mr. Walker" but would closely listen to the recommendation of law-enforcement agencies. Bush said he had not read transcripts of Walker's interviews with U.S. officials.
New York City Mayor Rudolph Giuliani, who on Sept. 11 nearly joined the more than 3,000 victims of the fallen World Trade Center, made it clear where he stands on Walker.
"When you commit treason against the United States of America, particularly at a time when the U.S. is in peril of attack and further attack, I believe the death penalty is the appropriate remedy to consider," he said Sunday.
Walker's execution would be a warning to others who want to turn to the other side, he said.
If Walker were to be tried, it could be in a civilian or military court, but the penalty in either case could be the same: death. Proving treason is difficult, however, and the fact that Walker joined the Taliban months before the Sept. 11 attacks could make the case weaker.
But his punishment in America's consciousness has already been decided: eternal disgrace.
"History as not looked kindly upon those have forsaken their countries to go and fight against their enemies," Attorney General John Ashcroft told senators last week.
But for now the future of the "battlefield detainee," as Walker is being called, is uncertain.
The Associated Press contributed to this story.