Veterans in Congress clean Vietnam War memorial: "We had a mission to do in Congress"

Reps. Seth Moulton, Sam Nunn and Don Davis — all members of the For Country Caucus — cleaned the Vietnam Memorial last week, despite an all night session. "Cleaning this wall today, I think, is a small testament to just the respect that we can pay for those who went before us, and that we have a legacy we need to carry on for them," Rep. Zach Nunn tells "Face the Nation with Margaret Brennan."