When: 1976 

Jenner won a gold medal at the 1976 Summer Olympics in Montreal, and set a world record in the process. There's nothing more fitting than his USA tank top and track shorts to tell every other country they can kiss his ass. You don't always want to dress like Uncle Sam, but at events like the Fourth of July or going to a U.S. Men's National Team soccer match, it's perfectly fine to let your red, white, and blue freak flag fly.