When I first heard this as a breaking news item (before I heard that it was Jewish school children targeted) the very first thing that came to my mind was that the shooter would turn out to be a peaceful muslim.
The bit about this being AQ related, I think, is bullsh*t. AQ as an organizational threat is largely nonexistent. They are gone. But they have lots and lots of sympathetic peaceful muslim followers who are more than willing to carry out stuff like this.
If AQ was still a threat then they would be doing stuff in the coordinated manner that has been their calling card in the past.
I have expressed surprise in year's past that AQ never did become more of a terror threat in the USA following 9/11. Face it, we are one big bag of soft targets in this country. It would be relatively easy for a half a dozen AQ gunmen to enter anywhere...take your pick: shopping mall, school, hospital, church, etc.)...seal off the exits and begin to kill off civilians shooting gallery style. It never happened. This amazed me. Looking back on it I can only assume that for the most part AQ as an organization was pretty small and we pretty much killed them off and put them on the run so that they could never become the big threat that they otherwise might have been.
9/11 was their high water mark. They killed a bunch of train travelers in Spain and a few subway rider in England but for the most part they were nothing after we killed off most of their leadership.
That said, the muslim threat will always be with us because that's what muslims do. Their religion dictates that infidels will be either converted, killed or made slaves. It is an evil religion from start to finish and its adherents will always be a threat. I would never turn my back on someone I knew to be a muslim. Never, ever.