“Who we are” serves other purposes. It allows the president’s followers to absorb the jingoism of less sophisticated people—all those vulgar crowds chanting USA! USA!—and refine it into the moral vanity they more highly prize. (Self-flattery is who they are.) Democrats have been bedeviled for decades by the canard that they are somehow less patriotic than conservatives. “Who we are” allows them to turn the tables, so long as who we are is Democrats. If, for example, you think that 99 weeks of unemployment insurance payments is about all we can afford, then you’re not just wrong, you’re un-American. You’re not who we are. It’s super-patriotism for the passive-aggressive. If we still had a House Committee on Un-American Activities we could rename it the House Committee on Activities of People Who Are Not Who We Are as Americans. 
Indeed, not who we are is as important to the president as who we are. Lately he has been using his word clump in a negative formulation. When Ebola briefly became the crisis of the decade a while ago, the president stood tall. “I put those on notice who think that we should hide from these problems,” he said. (It’s not clear who those people were—I’d need to see some direct quotes.) But the president made it clear who we were not: “That’s not who we are.” And people who oppose large subsidies for windmills and solar energy—maybe they think they’re Americans. No: “That’s not us. That’s not who we are.” Same goes for all those people who want to “eliminate health insurance for millions of Americans who are poor and elderly or disabled” just so they can give tax cuts to rich people—though again, I’d like to see a show of hands from the people who want to do this. Anyway: that’s who we are .  .  . not. 

Theologians used to speak of the Via Negativa—a philosophical method that tries to define God by ticking off all the things he isn’t, in a process of elimination. It turns out that even the president’s positive affirmations of “who we are” are essentially negative. The president and his supporters have embarked on their own via negativa, defining true Americans by eliminating, rhetorically, the ones who disagree with him. It’s an odd mission for a man who as a candidate told us there was no blue America or red America, only the United States of America. But that’s not who he is as a president.