Donald Trump is stuck. He is a brutally transactional politician who represents a coalition of ideologues. His instinct is to promise the moon, and he’ll say anything to get a vote — or just to get out of a room. He also knows, however, that he has no choice but to dance with the date that brought him. He can’t abandon the groups, interested parties and constituencies that put him in the White House to execute their agenda — to exercise their will. The problem comes when most voters don’t want what your partners hope to do with the power...