That's a tough one
You'd have possibly less deaths, but it would almost certainly involve children
I dunno though, I have no idea how these things would work out, but I'm guessing it would be at least AS bad as what happened, just different. Probably the only thing you'd have changed would be that you wouldnt have the image of the smoking/crumbling towers.
You'd have just as much death and carnage though, just on the ground