" The forces at work in healthy party politics are centripetal; they encourage factions and interests to come together to work out common goals and strategies. They oblige everyone to think, or at least speak, about the common good. In movement politics, the forces are all centrifugal, encouraging splits into smaller and smaller factions obsessed with single issues and practicing rituals of ideological one-upmanship. "

― Mark Lilla , The Once and Future Liberal: After Identity Politics