The Armed Forces Inaugural Committee coordinates events such as yesterday's wreath laying and yesterday's opening ceremonies at the We are One concert.
From PIC:
If you spend any time around the Capitol these days, you’ll see an unusual number of soldiers, Marines, sailors, airmen, and coast guardsmen in the area. While about 5,000 of these brave men and women in uniform are working with the Secret Service to provide security for the inaugural activities, 750 military personnel are working with the Armed Forces Inaugural Committee (AFIC) to provide ceremonial planning, logistics and publications support.
AFIC is a special committee authorized every four years by the Secretary of Defense to provide professional military support for presidential inaugurations. Its members include representative from all of the United States armed forces: Army, Marines, Navy, Air Force, and Coast Guard.