It is, from my perspective, less important today looking backwards as to why these militants decided they did it than to find them and bring them to justice, and then maybe we'll figure out what was going on in the meantime.
Turbulence: This is what pilots announce that you have encountered when your plane strikes an object in midair. You'll be flying along, and there will be an enormous, shuddering WHUMP, and clearly the plane has rammed into an airborne object at least the size of a water buffalo, and the pilot will say, "Folks, we're encountering a little turbulence. " Meanwhile they are up there in the cockpit trying desperately to clean water buffalo organs off the windshield.