In a thought-provoking new essay in New York magazine titled “America Wasn’t Built for Humans,” Andrew Sullivan takes account of our tribal moment, seeking to explain how the country became divided into two, warning of the grave dangers division represents, and offering a solution for reuniting us. Sullivan’s piece is better-argued and more coherent than Mark Lilla’s recent attempt to offer a shared vision for bringing America together, which roughly called for our politicians to embrace a common ethos.