How far would you go for love? Tonight, as we celebrate America's Independence, you're going to meet a man who was once considered one of our country's greatest heroes, and the woman who traveled all... See More
How far would you go for love? Tonight, as we celebrate America's Independence, you're going to meet a man who was once considered one of our country's greatest heroes, and the woman who traveled all the way to Afghanistan during wartime to be with him. But the fall from grace was hard and fast. Here's ABC's chief investigative correspondent Brian Ross. Reporter: Until tonight, few Americans have heard the story of what happened to Jim. Seen here from the back, heading into a firefight, dynamic, hard charging major in the green berets. He dressed and fought like a native and was once considered a key to winning the war in Afghanistan. You did go native, is that fair to say? Yes, I did. Reporter: But now as he walks the streets of Seattle, the 46-year-old gant is a broken man, ready to tell his story of how in just a few years' time he would go from being called an American hero, awarded the silver star to being labeled a disgrace to the military. Harsh words. Harsh words. Harsh words, yeah. Reporter: And you accepted it? I did. I did. Come on! Reporter: For some, gadget was seen as a modern American version of Lawrence of Arabia, who lived and fought with Arab tribes, idolized by gant himself. Any sentence that mentions T.E. Lawrence and me I'm proud of that. Reporter: For others, he was the character in "Apocalypse now," gone native, out of his mind. I'm not innocent. I did break the rules and I never said I didn't. You drank alcohol. I drank alcohol. Reporter: You had a civil woman living with you. Yes, yes. Reporter: She was one of America's most experienced war correspondents. Ann Scott Tyson, who would quit "The Washington post" and live her family behind who would secretly live with gant as his lover. Now they are married and going public with their account of HOV and war. A battlefield romance that violated U.S. Army rules and led to the end of gant's military career. We did fall in love. I would say over the course of about a week. About the third day he asked me if I would marry him. I still have the e-mail. The answer was ha, ha, ha. Reporter: You were serious? I was serious. Reporter: Tyson has written a book how they fell in love and literally went to war together, documented in hours of videotape she provided to ABC news. Much of it recorded in the heat of battle. Weren't you putting the woman you loved at great risk? Absolutely. We both knew there was a lot of risk involved in doing what we did. And I would do it again. In complete violation of army rules. Reporter: Gant was sent to Afghanistan in 2010. The major had proposed a way to win the war, by spending small teams of special forces to move in with and win the loyalty of the tribes, one tribe at a time. A strategy endorsed by general David petraeus and other top commanders who told gant and the green berets to push the envelope. They do have to stretch the pounds a bit. There's an expectation that they'll do some of that. It's celebrated as a quality. Reporter: Gant brought a small team to assimilate with the tribes in two small villages. Looking more like Osama bin laden than an army major. Protect your village, protect your valley, and protect your tribe. Tell everyone I did not come here to fight, I came here to help the people. But if someone wants to Fight, they know where I am. If you get into trouble and you need us, we will be there. He clearly had grit, gut and intelligence. Reporter: Gant got around red tape to head out automatic weapons to the tribal police unit. He didn't always fill out the paperwork to provide fuel for their vehicles or account for the cash payments for Afghan gunmen he tired for extra security. And gant and his men rarely wore their official body armor or even army boots. When you're carrying a 70-pound kit and helmet and trying to chase down insurgents who are in flip-flops and pajamas, you can't fight like that. Reporter: It was safer being dressed in Afghan clothes? Absolutely. Even the tactics, you could move further and faster, you could take cover more quickly. You could carry more ammunition and water. It was an absolute no-brainer. Reporter: And in a short time, his strategy began to pay off as the tribe's code of honor required them to protect the Americans as their welcome guests. When the Taliban opened fire on this small compound, the villagers joined the Americans in returning fire with a vengeance. You cannot let violence go unanswered. You have to be prepared to be more violent than they are. Because if you're not, they'll kill you. They'll kill you. Reporter: She was there during the battle and claimed she was never afraid. The Afghans kept shooting, even as one of their leaders was wounded. The Americans quickly came to his aid. I'll never forget the courage of Afghans like abu wally, to fight with the Americans side by side. That is what we needed to win in Afghanistan. It wasn't about body armor or weapons. It was going to be about how we treated them. And it worked in a big way. Reporter: The tribal leader took on gant like a son and gant nicknamed him sitting bull. And gant's village became one of the few examples of success in Afghanistan. Called by some the petting zoo because so many politicians and top commanders showed up for tours and photo-opes. As the senators, including John McCain walked around. Ann said she had to hide for fear they would recognize her. When he came, I stayed out of the picture. Reporter: At other times she was out in the open, trained to use weapons, and she says, the Taliban was overheard on radios talking about the woman they called gant's wife. We didn't want my presence there to be widely known. But at the same time, a lot of people knew about it. Reporter: Gant would letter be accused of putting his men at risk to keep Ann safe. I never lost a man or left the battlefield defeated. Reporter: Perhaps the most important test for his strategy came after four U.S. Soldiers were killed in other parts of the country when Afghan counterparts became angry. Gant told his men he was heaving the compound to walk around among the villagers to send a message he trusted them. You have to trust me. I'm putting your lives in my Hands right here, saying I'm going to protect you. Okay? If you don't feel a little fear in your heart right now, you're Stupid. You're just not smart. You must trust the people you're with. Therein lying your security. He lived by that. Our lives were at risk, but they were safer the more you lived by that. Reporter: So you were safer by breaking the rules than following the rules? Ytin this case, yes. Reporter: But they were the constant target of Taliban, and hit a roadside bomb. But in another attack, gant walls injuwas injured. But he down played his injury, ignoring another army rule. Should you have done that? If you're a rule maker, no, I shouldn't. But I had to break the rules to be as successful as I wanted to be, yeah, I did. Reporter: But ultimately someone would write him up and gant would discover his enemies were not just among the Taliban. You're in a very, very, very,
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