Democracy isn’t possible without the rule of law — the idea that consistent principles, rather than a ruler’s whims, govern society. You can read Aristotle, Montesquieu, John Locke or the Declaration of Independence on this point. You can also look at decades of American history. Even amid bitter fights over what the law should say, both Democrats and Republicans have generally accepted the rule of law. President Trump does not. His rejection of it distinguishes him from any other modern American leader. He has instead flirted with Louis XIV’s notion of “L’état, c’est moi”: The state is me — and I’ll decide which laws to follow.