On July 17 Jeff was in his kitchen when the phone rang. It was a producer from CNN asking if he could go on air to talk about the Malaysia Airlines 777 that had just gone down over Ukraine. He’d spent so much time thinking about Ukraine and MH370 that it took him a moment to realize that she was talking about a completelely different airplane.

The details were still sketchy, but it seemed that in the late afternoon, Ukraine time, Malaysia Airlines Flight 17 had been flying from Amsterdam to Kuala Lumpur when it had exploded in midair. Initial reports suggested it might have been shot down by a surface-to-air missile while flying over territory held by Russia-backed rebels.

A Malaysia Airlines 777. Ukraine. Russia. The echoes seemed too overwhelming to ignore. Boeing 777s are among the most reliable airplanes in the world; none had ever been lost mid-flight before. There were 15 Malaysia Airlines 777s at the start of 2014, out of some 18,000 registered aircraft in the world, and two had come to grief under mysterious circumstances in less than five months.

But on air at CNN, all the other aviation analysts agreed that of course the destruction of MH17 so soon after the loss of MH370 could only be a freak coincidence. What connection could there possibly be?

It was soon established that the plane had been shot down by a surface-to-air missile. A 150-pound shrapnel-laced warhead had torn open the aluminum airframe, scattering passengers and crew into the 500 mph slipstream. In most airplane crashes, the question is: what happened? This time, it was: who did it, and why?

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