America’s 250th birthday celebration feels like a child’s birthday party ruined by fighting between two soon-to-be-divorced parents. What should be a benign celebration of shared, if slightly boring, values has become a fully partisan affair.  In part, this is due to the president’s determination to make it all about himself. But the agita surrounding America 250 is not just about President Donald Trump’s garish White House UFC fight or poorly attended “Great American State Fair.” It is a reflec