Shocking. RIP to the dead.
The problem is, American Peresidents swear an oath to defend the constitution, part of that constitution is the right to bear arms, so probably political suicide to even go there.
The problem is also that the genie is out of the bottle. There are millions of guns out there, so even if they were to be banned, who's going to try and get them handed in? There's is also a huge arms industry.
But my personal opinion, is while I can almost understand the desire to own a hand gun for self defence, why anyone needs a military grade assault rifle is beyond me.