I hate to get involved with threads on this topic since I have worked on this issue for so long, but I just wants to correct one thing. Fully automatic weapons are not illegal. You only need to acquire a special license and pass a background check to get one. It is illegal to manufacture a new fully automatic weapon in this country, but there are certainly some in circulation, I've seen plenty at gun shows. But it doesn't matter all that much anyway since you can empty a 30 round magazine in a semiautomatic pistol in 10-12 seconds. If you bump fire a semi-auto rifle you could probably empty a 100 round magazine in the same amount of time.
One other thing, the notion about bad people accomplishing their misdeeds even if they didn't have guns available? Research suggests that's not true. Look at suicide for example. Most people who attempt suicide fail. Only a small percentage use guns to attempt it, but as you might guess, most of those people are successful. It's sad.
I really don't think it's the power of the NRA anymore either, they don't have much sway anymore. I think when it comes to gun violence in this country most are just resigned to our fate unfortunately as a lot of the comments in this thread indicate.