Washington is one of the only places in America where an election transforms the city’s social life. Plenty of people live here with no regard for who occupies the White House, but a lot of social networks get rewired when a new president comes to town and brings along thousands of ideological kin. In the Kennedy and Johnson eras, official Washington took its cues from the White House: Glamorous dinner parties were in vogue under JFK, followed by more down-home barbecues under LBJ. No matter the president, though, guest lists tended to span both parties, and the fraternizing helped keep the government’s gears and levers well-enough oiled.