Pff...if any given country/place in the world suddenly had a Diarrhea Epidemy, ISIS would even dare to claim that as their actions. ISIS only wants you to have fear, so they will say whatever and use whichever scenario possible to give you fear.
My Comment:
That said, in USA even a fucking child can get a fucking machinegun. And honestly? Americans aren't that peaceful nor mentally stable as anyone thinks. Otherwise you wouldn't have the same exact scenario in schools all over the country.
I don't care if this offends you, but the truth is that, acquiring guns in USA is as easy as acquiring Bubble gun, I mean, Bubble Gum.
Not happy for what it happened, but C'mon, is not that hard to understand "WHY" a coward had GUNS in the first place, and "WHY" the fucking hotel didn't revised his packs or whatever he used to carry them.
And even "HOW" he had access to them in the first place.