But according to Obama, those two weeks make all the difference.

“You know, I noticed that when we were in the gym together, you were working out a little harder than me,” Obama joked when Woodruff told him about their age gap at a press conference as part of his 10 day trip to Southeast Asia. “So those two weeks clearly are making a difference.”

Besides gym workouts, Obama and Woodruff also share having come of age during the Vietnam War. The president reflected on that time at today’s press conference in the city of Vientiane, during his historic visit to Laos.

“Because we’re the same age, you’ll recall that at the peak of the war, we were still too young, I think, to fully understand the scope of what was taking place,” said Obama.

“It was the tail end of the war, where we’re entering high school and starting to understand the meaning of it,” he continued. “I think the debate had raged. Even those who had been strong supporters of the war recognized there needed to be some mechanism to bring it to an end. So I can’t say that I was so precocious that I had deep thoughts about it at the time, other than the images that we all saw on television.”

Obama later said that, in retrospect, the United States was on the “right side of history” in the Cold War but that in focusing on “defeating an expansionist and very aggressive communism, [we] didn’t think through all the implications of what we did as policymakers.”

From 1964 to 1973, the United States conducted a secret bombing campaign in Laos, on Vietnam’s western border, dropping over 2 million tons of explosives in 580,000 bombing missions, making Laos the most heavily bombed country per person in history. Earlier this week, in his visit to the ASEAN summit, Obama announced $90 million in funding will go toward the removal of unexploded bombs still hidden in the country.

But the president acknowledged that, regardless of “what happens in the White House and decisions made by policymakers,” those who served in Vietnam are American heroes.

“When our men and women in uniform go into action and put their lives on the line and they’re carrying out their duty, my attitude is they’re always heroes,” Obama said, “because they are saying that ‘I am willing to do whatever it takes, what my commander-in-chief has ordered, in order to keep the American people safe.’”

“And by definition, their job is to put their lives on the line and make sacrifices, both seen and unseen, that have long-standing ramifications,” he added. “And that act of sacrifice is heroic.”

ABC’s Bob Woodruff and John Parkinson contributed to this report.