In her Tuskegee address, at least Michelle Obama urged the graduates not to be daunted by slights (and more meaningful obstacles, like rotten schools). Even though she didn’t mention the word, what she was talking about was “microaggressions,“ the trendy term on college campuses for often inadvertent offensiveness.

The underlying premise of the microaggression is that only people who belong to certain select groups ever suffer indignities or humiliations, when they are, of course, inherent to the human condition. George Orwell once said that every life seen from the inside is a series of defeats.

The microaggression, properly understood, is a sign of progress. From chattel slavery to Jim Crow to innocent misunderstandings and occasional rudeness is a vast leap forward. But the logic of the microaggression increasingly defines the Democratic party, because identity politics needs the oxygen of perpetual grievance.