LONDON — Britain wrapped up a joyful four-day tribute to Queen Elizabeth II on Sunday with street fairs, picnics and a pageant, after a star-studded Saturday night concert at Buckingham Palace that offered a pop-culture mash-up of Rod Stewart performing Neil Diamond’s singalong “Sweet Caroline.”
Good times, as the song says, never seemed so good.
But if millions of Britons reveled in the queen’s Platinum Jubilee — or at least in the lazy pleasures of a late-spring, long weekend —…