On August 6, 1945, the B-29 bomber Enola Gay dropped an atomic bomb on the city of Hiroshima. Twelve men were on that flight. Some chose to keep a low profile and others spoke out about their place in history. Almost all had something to say after the war.

The 509th Composite Group was formed by the U.S. Army Air Force to deliver and deploy the first atomic bombs during World War II. The group was segregated from the rest of the military and trained in secret. Even those in the group only knew as much as they needed to know in order to perform their duties. The group deployed to Tinian in 1945 with 15 B-29 bombers, flight crews, ground crews, and other personnel, a total of about 1770 men. The mission to drop the atomic bomb on Hiroshima, Japan (special mission 13) involved seven planes, but the one we remember was the Enola Gay.

Captain Theodore Van Kirk, Navigator

Air Force captain Theodore "Dutch" Van Kirk did not know the destructive force of the nuclear bomb before Hiroshima. He was 24 years old at that time, a veteran of 58 missions in North Africa. Paul Tibbets told him this mission would shorten or end the war, but Van Kirk had heard that line before. Hiroshima made him a believer. Van Kirk felt the bombing of Hiroshima was worth the price in that it ended the war before the invasion of Japan, which promised to be devastating to both sides.

I honestly believe the use of the atomic bomb saved lives in the long run. There were a lot of lives saved. Most of the lives saved were Japanese.

In 2005, Van Kirk came as close as he ever got to regret.

I pray no man will have to witness that sight again. Such a terrible waste, such a loss of life. We unleashed the first atomic bomb, and I hope there will never be another. I pray that we have learned a lesson for all time. But I'm not sure that we have.

After the war, Van Kirk got a masters degree in chemical engineering and worked for DuPont until his retirement. Van Kirk passed away in 2014.

Major Thomas Ferebee, Bombardier

Thomas Ferebee pushed the button that dropped the bomb on Hiroshima. He slept in the plane both before and after he did his part. After the war, Ferebee stayed with the Air Force, serving in the Strategic Air Command and in Vietnam. He retired as a full Colonel.

Colonel Ferebee, who retired from the Air Force in 1970, always argued that the Hiroshima bomb was necessary. "I'm convinced that the bombing saved many lives by ending the war," he told Newsweek magazine in 1970.

That doesn't mean he had no opinion on the further use of such weapons.

"Now we should look back and remember what just one bomb did, or two bombs," he told The Charlotte Observer in 1995, the 50th anniversary of the bombing of Hiroshima. "Then I think we should realize that this can't happen again."

Colonel Ferebee died in Florida in 2000, at the age of 81.

Lieutenant Jacob Beser, Electronic Countermeasures

Army Air Force radar specialist Jacob Beser was the only man who served on both the Enola Gay in the Hiroshima bombing mission and the Bock's Car three days later when its crew bombed Nagasaki. He couldn't look at the detonation of the bombs because he was charged with monitoring for outside signals that could have detonated the bomb early and monitoring for signals of the proper detonation. This is addition for keeping an eye on radar for any enemy planes.

In this 1985 interview for the Washington Post, Beser was asked if he would do it again.

Given the same circumstances in the same kind of context, the answer is yes. However, you have to admit that the circumstances don't exist now. They probably never will again. I have no regrets, no remorse about it. As far as our country was concerned, we were three years downstream in a war, going on four. The world had been at war, really, from the '30s in China, continuously, and millions and millions of people had been killed. Add to that the deliberate killing that went on in Europe, [and] it's kind of ludicrous to say well, geez, look at all those people that were instantly murdered. In November of 1945 there was an invasion of Japan planned. Three million men were gonna be thrown against Japan. There were about three million Japanese digging in for the defense of their homeland, and there was a casualty potential of over a million people. That's what was avoided. If you take the highest figures of casualties of both cities, say, 300,000 combined casualties in Hiroshima [and] Nagasaki, versus a million, I'm sorry to say, it's a good tradeoff. It's a very cold way to look at it, but it's the only way to look at it. Now looking into tomorrow, that's something else again. I don't have any pat answers for that.

After the war, Beser was an engineer at Sandia Laboratories where nuclear research continued and at Westinghouse where he worked on classified projects for the military. He retired in 1985. In 1988, Beser wrote a book called Hiroshima and Nagasaki Revisited. He died of cancer in 1992 at age 71.

Sergeant Joseph Stiborik, Radar Operator

There isn't a lot of biographical information available on radar operator Joe Stiborik, except for some of his reminiscences of the mission.

Joe Stiborik remembered the crew sitting in stunned silence on the return flight. The only words he recollected hearing were Lewis's "My God, what have we done." He explained, "I was dumbfounded. Remember, nobody had ever seen what an A-bomb could do before. Here was a whole damn town nearly as big as Dallas, one minute all in good shape and the next minute disappeared and covered with fires and smoke...There was almost no talk I can remember on our trip back to the base. It was just too much to express in words, I guess. We were all in a kind of state of shock. I think the foremost thing in all our minds was that this thing was going to bring an end to the war and we tried to look at it that way."

Stiborik died of a heart attack in 1984 at age 69.

2nd Lieutenant Morris Jeppson, Ordnance Expert

Morris Jeppson was only 23 years old when he was assigned to accompany the atomic bomb on the Enola Gay. It was his duty to arm the bomb and make sure it would work. Jeppson had the power to abort the mission if it didn't. It was his first and last mission of the war. Jeppson had worked in developing the mechanics of the bomb, and after the war he continued on the nuclear path. He studied physics at Berkeley and worked in the radiation laboratory there. Then he worked on developing hydrogen thermonuclear weapons at Lawrence Livermore Laboratory. Jeppson went on to invent and market hi-tech machinery for medical and industrial uses.

In 1995, Jeppson looked back at the Hiroshima mission.

Until the 509th reunion that year Jeppson hadn't given the mission much thought. "Those bomb plugs were just kicking around in a drawer" for years, he says. Still, he maintains that dropping the bomb on Hiroshima was a necessary means to help end the war. He points to wartime concerns that Germany was developing nuclear bomb technology. "If that had happened, the world would be an entirely different place (today)," he says.

Jeppson passed away in 2010.

Private Richard Nelson, Radar Operator

Richard Nelson was the youngest of the Enola Gay crew. He was 20 years old in August of 1945. He relayed the news of the atomic bomb to his superiors in code, who forwarded it to President Truman: "Results excellent." After the war, Nelson got a degree in business administration and made a career as a salesman. Fifty years later, he had no regrets about his part in the mission.

"War is a terrible thing," he told The Riverside Press-Enterprise on the 50th anniversary of the bombing. "It takes and it destroys. Anyone feels sorry for people who are killed. We are all human beings. But I don't feel sorry I participated in it. If I had known the results of the mission beforehand, I would have flown it anyway."

Nelson died from emphysema in 2003 at age 77.

Staff Sergeant Robert Caron, Tail Gunner

Enola Gay tail gunner Bob Caron wrote a book about the mission called Fire of a Thousand Suns. Despite his description of the bomb's effects, he never regretted being part of the mission.

In an interview with the Rocky Mountain News published two weeks before he died, Mr. Caron said he had no regrets about his role in the World War II bombing. "No remorse, no bad dreams," he said. "We accomplished our mission."

Caron died of pneumonia in 1995. He was 75 years old.

Staff Sergeant Wyatt Duzenbury, Flight Engineer

Wyatt Duzenbury kept tabs on the Enola Gay's engines and other systems while others tended the bomb and the mission itself. He considered it an honor to be chosen for the secret bombing mission that was to shorten the war. After 1945, he stayed with the Air Force. In his retirement, he looked back at the mission.

...he told the Lansing State Journal in 1985, "We were told to go, cranked up, dropped it, and came home." He told the newspaper that he didn't feel guilty about his mission, but did "not feel good about the 100,000 people who died." In an earlier interview, he said, "Personally, I feel that if we hadn't dropped that bomb, and the other crew hadn't dropped its bomb on Nagasaki, it would have cost thousand of US soldiers' lives establishing a beach head for the invasion of Japan."

Duzenbury died in 1992 at age 71.

Sergeant Robert H. Shumard, Assistant Flight Engineer

Robert Shumard assisted flight engineer Wyatt Duzenbury in keeping the Enola Gay running. In a 1960 interview, Shumard said he didn't feel honored to do what they did, but he felt honored to be selected for the mission. And given the circumstances, he would do it again.

"Nobody actually wants to cause the destruction we caused," he said. "But it was through a necessity rather than a wanton type of destruction. It was something that had to be done. As much as a man has gangrene in his leg, and they have to cut it off. It's something that has to be done. It was a cancer in the world situation that had to be removed, that's all."

Captain Deke Parsons, Weaponeer

Naval gunnery officer William "Deke" Parsons was pulled from sea duty to work on the Manhattan Project in 1943. He helped turn the nuclear bomb into a weapon of war, from development to assembly to delivery. He armed the first atomic bomb while the Enola Gay was airborne. After the war, Parsons continued in nuclear weapons development, rising to the rank of Rear Admiral. He oversaw the Operation Crossroads nuclear testing project and also served on the Atomic Energy Commission. Parsons witnessed seven of the first eight nuclear explosions. There are no quotes available from Parsons as he was still serving in the Navy when he died of a sudden heart attack in 1953. He was 52 years old.

Captain Robert Lewis, Co-Pilot

Air Force flier Robert Lewis was a pilot first and foremost. He was upset that commander Paul Tibbets had named his plane the Enola Gay. But he was also dedicated to the mission, and earned Tibbets' respect despite the animosity between the two. Lewis wrote a diary of the mission in a notebook during the flight to Hiroshima, against orders. He later sold it for $37,000. It was resold in 2002 for almost ten times that much. He is often quoted:

"As the bomb fell over Hiroshima and exploded, we saw an entire city disappear. I wrote in my log the words: 'My God, what have we done?'"

Some sources say that quote was a revision after the fact. Later in life, Lewis defended the mission.

Over the past half century, some of the crew have returned to the city to take part in the annual commemoration celebrations. Lewis never did. For him "it was just a job of work. I helped make the world a safer place. Nobody has dared launch an atomic bomb since then. That is how I want to be remembered. The man who helped to do that."

Lewis died of a heart attack at age 65 in 1983.

Colonel Paul Tibbets, Commander and Pilot

Lieutenant Colonel Paul Tibbets was chosen to head the bomb delivery mission in September of 1944, and he selected the rest of the crew. At that time, the Manhattan Project was preparing to drop a bomb on Europe as well as Asia. After the mission, Tibbets remained in the Air Force until 1966, achieving the rank of Brigadier General. He worked as an aviation executive until his retirement in 1970.

In a 2002 interview with Studs Terkel, Tibbets said he never had second thoughts about the mission:

Number one, I got into the air corps to defend the United States to the best of my ability. That's what I believe in and that's what I work for. Number two, I'd had so much experience with airplanes... I'd had jobs where there was no particular direction about how you do it and then of course I put this thing together with my own thoughts on how it should be because when I got the directive I was to be self-supporting at all times. On the way to the target I was thinking: I can't think of any mistakes I've made. Maybe I did make a mistake: maybe I was too damned assured. At 29 years of age I was so shot in the ass with confidence I didn't think there was anything I couldn't do. Of course, that applied to airplanes and people. So, no, I had no problem with it. I knew we did the right thing because when I knew we'd be doing that I thought, yes, we're going to kill a lot of people, but by God we're going to save a lot of lives. We won't have to invade [Japan].

Tibbets died in 2007 at age 92. He had requested cremation and no physical memorial, because it would become a pilgrimage site for nuclear protesters.

This post originally appeared in 2010.