It's a tragic year indeed.
I don't believe gun control is a viable solution to a problem like this in the US. In other countries it may be much more effective, but when you consider the countless millions of firearms that are in private circulation in the US, it would be impossible to collect even a fraction of them. The only ones that would give them away would be those who are willing to submit to the law, and it would leave a bunch of nutjobs sitting on private arsenals, waiting to take advantage of the situation.
It deeply disturbes me though, that the society we live in obsesses so much with violence that it is hatebreeding all of these desensitized psychopaths with zero regard for life in any form. Something is terribly wrong at a base-level to be causing such happenings.