Read "Whatdoesitmean.com."  There is an article that it was retaliation.  Sometimes I don't know what to make of that site, but, I don't completely rule out their explanation of world events.  It's kind of like 5eyes, for the regular readers.  Lately, a lot of what they reported on, has been coming out.  (I know, I know, I know, we aren't supposed to take that site seriously, but if they are prescient on a lot of things.)