“This is the way the flag would fly as we run into battle.”
The full-color U.S. flag cloth replica is worn so that the star field faces forward, or to the flag’s own right. When worn in this manner, the flag is facing to the observer’s right, and gives the effect of the flag flying in the breeze as the wearer moves forward.
When the flag is affixed to the side of a vehicle of any kind (e.g.: cars, boats, planes, anything that moves), it should be oriented so that the canton is towards the front of the vehicle, as if the flag were streaming backwards from its hoist as the vehicle moves forward. Therefore, U.S. flag decals on the right sides of vehicles may appear to be “reversed”, with the union to the observer’s right instead of left as more commonly seen.
The rule dates back to the Army’s early history, when both mounted cavalry and infantry units would designate a standard bearer, who carried the Colors into battle. As he charged, his forward momentum caused the flag to stream back. Since the Stars and Stripes are mounted with the canton closest to the pole, that section stayed to the right, while the stripes flew to the left.