FAQ:
https://docs.google.com/document/d/11nZZj4GxYI89u5FisF-uGqKvrJ2r40rZ4Uu5Fn1PvGw/edit
A sentinel at the Tomb of the Unknowns at Arlington National Cemetery briefly interrupts his routine of 21 paces to warn a visitor who has hopped over the chain surrounding the Tomb's plaza.
The men in the yellow t-shirts are WWII veterans from Tuscaloosa, AL touring the Washington D.C., area courtesy of the Honor Flight Network and the Tuscaloosa Rotary Club.