John Adams’s Nixon in China, first performed in 1987, is usually regarded as launching the concept of “CNN opera”: music-theatre works that dealt with contemporary events and recent history, often with protagonists who were still alive when they were first portrayed on stage. But arguably the genre had begun the previous year, with the staging at the New York City Opera of X: The Life and Times of Malcolm X, by the composer and pianist Anthony Davis, based on the life and death of the militant human rights campaigner Malcolm X.