Over the past year, the NFL has been a hub of controversy, with domestic violence scandals and damning reports on concussions and other catastrophic injuries rocking the organization, and its fans, to the core. Taking a retrospective look at the NFL, Ronnie Lott, SI's Peter King and Jon Greenberg examine the ways the organization—and the society that surrounds it—has changed and how we can all rediscover the joy in sports.