Millions of Americans are remembering the 9/11 terror attacks that took place exactly 23 years ago. “All of us, of every age, should grieve together today for those nearly 3,000 Americans who died,” Rep. Jake Auchincloss, D-Mass., says on “The Hill.” Auchincloss served in Afghanistan as a Marine. Moderator Blake Burman speaks with Auchincloss about the biggest threats currently facing the U.S.