Our culture has always had tribalism--different political parties, preferred media outlets, and shifts in positions when politically advantageous. But now our country is facing a far deeper, far more serious existential crisis. We're reaching a point where we've lost faith and trust in the institutions that have held us together. Even more worrisome is that we've lost a shared sense of truth. What happens to a nation when half of us believe different facts than the other half? In Them, bestselling author and U.S. Senator Ben Sasse argues that the problem is far deeper than politics or even any one politician. Across the nation, local communities are evaporating. The basic framework for everyday life -- family, work, neighborhoods, friends, trust-- is collapsing or, in the case of work, being vastly redefined. Our citizens have become alienated from each other, angry, and lonely. As our traditional tribes are falling apart, Sasse argues, frustrated and displaced Americans are trying to fill the vacuum with Anti-tribes on social media and cable news, surrounding ourselves with people we already agree with and identifying a common enemy. We are stuck in a loop of loneliness, outrage, and anger.Sasse offers his own prescription for addressing this challenge, calling for a radical effort to rebuild and remake the institutions that are foundering within communities and a nationwide discussion and understanding of just how monumental this challenge is.