More than 600 Vietnam veterans and their families gathered on Capitol Hill Wednesday for a ceremony hosted by leaders of both the House and Senate commemorating the 50th anniversary of the Vietnam War. Defense Secretary Ash Carter, who spoke at the event, thanked the “7.2 million living Vietnam-era veterans, their fallen comrades-in-arms, and the families of all who served,” for their sacrifices, noting their service helped make the country stronger. “One of the reasons the United States has excelled is that, as a nation, we learn and innovate,” said Carter. “And, one reason why we have the finest fighting force the world has ever known is that our military is a learning organization.” He emphasized two important lessons learned from Vietnam. “First, we leave no one behind,” he said. Though other countries have a similar ethos, “There are few that have such a steadfast and sustained commitment.” He noted the Defense Department has some 650 people “devoted” to searching for, recovering, and identifying service members who remain missing, including the more than 1,627 still missing from the Vietnam War. Second, he said the nation must support its troops “regardless of our feelings about the war.” That’s a lesson he acknowledged, “some learned the hard way in the Vietnam era.” More than 58,000 Americans were killed during the war and more than 153,000 were wounded. (DOD release) (Video of House Speaker John Boehner’s comments during the ceremony.) (Transcript of Senate Majority Lead Mitch McConnell’s remarks.)