We must fight Vladimir Putin as determinedly as he fights us. We will stop him when we stop letting our partisan and personal interests expose our national security interests, even the integrity of our democracy and the rule of law, to his predation. We will stop him when we start believing in ourselves again and when we remember that our exceptionalism hasn’t anything to do with what we are—prosperous, powerful, envied—but with who we are: a people united by ideals, not ethnicity or geography, and determined to stand by those values, not just here at home but throughout the world.