Last week, I spent time with the gifted young political theorist Yascha Mounk, who had just become an American citizen. He told an audience at the Chicago Council on Global Affairs that while he did not discount our country's problems, particularly the costs of a "racial hierarchy," the United States was genuinely different because it rejected a "mono-ethnic and mono-cultural" definition of nationality. "In America," he said, "there is an idea that you can have an accent and be American, you can have immigrated and be American." It's another reason I love this country.