Unfortuantely, the anti's will seize this as an opportunity to soapbox about more gun control.
I disagree wholeheartedly. I really don't think they will try to use this one.
We all know that this incident shoots any arguments they might have full of holes. I think they do too. Any anti gun zealot will avoid bringing this particular incident up because, statistically speaking, gun control encourages incidents like this one. It would be very difficult for anyone to argue that gun control would have prevented this tragedy from happening (as you said, Dauherty16). Gun control would have gauranteed that there would be no opposition at all to the shooter (who took an awful risk by going in there armed and assuming no one would be carrying - I think he knew a lot of the people there would not be armed from personal experience with them - many used to be his coworkers).
It's knowing that victims will not be armed that proliferates crimes like this (that's why so many occur in colleges and schools - these are well known no gun zones. No gun zones=umarmed targets). Even the antis know that gun control is a root cause of armed criminals going after unarmed victims with a bold sense of impunity. The utopia they envision is a society where there are no guns at all - unfortunately, they don't have an answer for the problem of keeping guns out of the hands of criminals if guns were made illegal to everyone.
I know a few anti gun people - and in the past, many of them would try and bring up incidents like this one to make their argument but not so much anymore. The ones I know realize that these "crazies" that short circuit and go on shooting sprees only hurt their argument for more gun control - especially if a legally armed citizen intervenes, as happens more and more often these days - and the news outlets don't seem to report those with as much fanfare.
Check this link to see how often this really happens:
And it would be interesting to see if, in the future, the government made companies responsible for the safety of its employees if concealed carry is forbidden on site and an armed nut job showed up. By that I mean - if at some point in the future - the family of a dead victim could sue such a company with a no CC policy for failing to protect their deceased loved one.