Comedian and pundit Bill Maher took a vicious shot at Bill O'Reilly out of nowhere, taunting his fall from Fox News mainstay to podcast host and O'Reilly shot back with a defense of his own. On Friday night's edition of HBO's Real Time with Bill Maher, the interview guest was country music singer-songwriter Kenny Chesney, who enters the Country Music Hall of Fame this year and co-authored the new book Heart Life Music.