EVERYTHING OLD IS NEW AGAIN: Beyonce and the Return of Radical Chic.

When Sha-Na-Na took the stage at Woodstock in 1969 in T-shirts, gold lamé Elvis jackets and Brylcreemed pompadours, they were correctly understood to be an “oldies act,” celebrating a culture that had died five years earlier — when the Beatles’ arrival in America in 1964 consigned ‘50s-era rock and roll to the dustbin of history. How did a once-fast-changing pop culture become so permanent that Beyonce is glorifying the Black Panthers, whose heyday was 45 years ago, even as the top film in the country is a sequel to a movie made almost 40 years ago?