Detail by painful detail, the CIA is coming to grips with one of the most devastating episodes in its history, a botched cloak-and-dagger flight into China that stole two decades of freedom from a pair of fresh-faced American operatives and cost the lives of their two pilots. In opening up about the 1952 debacle, the CIA is finding ways to use it as a teaching tool. Mistakes of the past can serve as cautionary tales for today's spies and paramilitary officers taking on al-Qaida and other terrorist targets. At the center of the story are two eager CIA paramilitary officers...