Fidel Castro just turned 90 two days ago — no longer as we remember him, ever youthful, ever vigorous. What did he have that fascinated so many of us for so long, that let him dominate Cuba and from that small base to shake the whole world? And threatening to do more than just shake it, in October 1962. Like him or hate him, you have to acknowledge that his was a personality hard to resist, even by those among us who should have known better.

And today, 150 years later, the Paris Commune of 1871 continues to resound as “a synonym of social struggle,” inspiring the slogans of radical democratic movements from Hong Kong to Spain to New York.