Augusto Pinochet led a military coup that topped Chile's elected President, Salvador Allende, on September 11, 1973. It was a bloody affair, and Allende was one of those who died. When Pinochet died yesterday, thousands of demonstrators celebrated in the streets of Santiago, Chile, the country he ruled for almost 20 years. There were some violent encounters with police and with mourners. Pinochet was 91 years old, and his death came--ironically--on International Human Rights Day.