Cover Story | The killing of four Cuban-American private rescue pilots by Fidel Castro's air force has provoked official, after-the-fact outrage from the U.S. government. But under-oath testimony shows that government officials knew Cuban MiGs were bearing down on the Cessna pilots; they did nothing. American interceptors were ready for takeoff; they were left on the runway. The pilots could have been warned; they weren't. The government's response: "A poor assumption." What happened in the crucial moments before the fatal shootdown? The details are "classified." But there's enough information available to suggest, at best, a government conspiracy of silence.