Transcript for Saluting the American heroes in Vietnam

Finally tonight here, the reunion here in Hanoi. We have journeyed here before, to what's left of the prison known as the Hanoi Hilton. Where John McCain and so many other Americans were held prisoners of war. The rain pouring as we walked through. The prison cells, so little light. The bars on the windows. The concrete floors and narrow beds. John McCain was 31. An enemy missile would tear one of the wings off his bomber. He ejected. The sheer force of that moment breaking both of his arms and one of his legs. What is your name? Lieutenant commander John McCain. Reporter: And in what's left of the prison now, we discover a book. You can see here some of the American pilots who were arrested between 1964 and 1973. The faces of the prisoners from all over the U.S. And outside the Hanoi Hilton today, the men of foxtrot 21. Marines who fought in Vietnam. Their battalion became known as the ghost battalion, because they lost so many. More than 50 years later, a reunion here in Vietnam. With help from the greatest generations foundation. Lieutenant colonel James page is here from Florida. Who remembers operation harvest moon, a battle that still haunts him. I lost 12 Marines that day. I was the company commander and that has bothered me ever since. So, I hope to go down and get piece when I two stand on the battlefield. I want to bury that. Reporter: Americans visit every day here. Remembering a polarizing time in America, and determined to remember those who served, too. We all lived so much of that, so, to come here and almost, you know, remember some of the young men that we grew up with. It's important. Reporter: Joann walker's husband served in Vietnam. We talked more about it when we got here than we had ever. And it's emotional, because it was difficult, in a lot of ways. Reporter: And tonight, the veterans here showing us something else that was important to them on this trip. Getting the chance to meet some of the soldiers who they once fought against here in Vietnam. All of the men together, through shared pain. And tonight, through shared peace. It means a lot to us, it's closure for us. We lost a lot of people over here and we got some great people here today and just means a lot to us. We thank them for their service and we thank them for sharing that moment with us today. I'm David Muir. I hope to see you right back here tomorrow night. Good night. Night.

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