Defense Secretary Ash Carter and congressional leaders are thanking Vietnam War veterans for their service and presenting pins to dozens of veterans at a Capitol ceremony.

House Speaker John Boehner and Senate Majority Leader Mitch McConnell joined lawmakers at a ceremony Wednesday marking 50 years since U.S. ground troops arrived in Vietnam.

The ceremony comes a day after President Barack Obama held an unprecedented meeting with the head of Vietnam's Communist Party as the U.S. presses to conclude talks on a groundbreaking Asia-Pacific economic pact.

Former Defense Secretary Chuck Hagel, himself a Vietnam veteran, told the Capitol crowd that he and other veterans feel a special bond. Hagel adds that he is grateful that the nation's attitude toward veterans has greatly improved since he returned from Vietnam.