No, people will always kill other people, that is the unfortunate truth of human nature. That doesn't mean there aren't multiple problems here, and each one with multiple solutions.

Our lawmakers know just as well as we do, that more laws won't fix events like these, but better messaging ("See something say something"), better trained police officers, etc.. these are things that are controllable, changeable, and have a hugely positive impact on preventing horrible things like this from happening.