A fair amount of detail has been gathered about the shooting down of Malaysian Airlines Flight 17 on July 17, 2014, in eastern Ukraine, which killed all 298 people aboard. The plane was hit by a Russian-made Buk missile launched by the 53rd Anti-Aircraft Missile Brigade based at Kursk, Russia. An investigation has identified four men — three Russians and one Ukrainian — who helped bring the Buk launcher to eastern Ukraine. But a missing piece has been: Who was responsible, and who approved?

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