Beyonce, Jay-Z, Katy Perry, John Mayer and other stars at 2013 Presidential Inauguration

Slideshow posted in Photos | Monday, January 21, 2013

12 of 25: Kelly Clarkson performs 'My Country 'Tis of Thee' after President Barack Obama's ceremonial swearing-in ceremony during the 57th Presidential Inauguration. (Watch a video of her performance.) ( Photo / ABC News)