I don't know if my high school was particularly lax, but students were allowed to chew gum in the halls, cafeteria, and, unless a teacher specifically objected, in class. One time after an assembly they handed out gum to every student as they left. I later learned that there was an administration-led drive to ban gum in the school and that handing out gum to every student was a way of testing the current policy. If the gum showed up stuck to the bottom of chairs and desks or became a nuisance they would have all the justification needed to ban gum permanently. That didn't happen though, students enjoyed their gum and disposed of it properly and the ban was given no further consideration.
Since Obama's election there has been a well documented spike in sales of assault weapons and other accessories that were previously banned. The fear is that Obama and a Democratic controlled congress will reinstate an assault weapon ban. So we have a statistical spike to work from and some solid facts on which to base our laws. In the next year or two if there is a spike in the use of assault weapons to commit crimes then IN MY OPINION we do need laws to make those types of weapons much harder for people to obtain. I honestly hope we don't see an increase in crime involving assault weapons. I'd like to think that there are enough responsible gun owners out there that such a ban isn't necessary. We'll see.
It's been pretty well documented that the assault weapon ban is largely an aesthetic ban as there are unbanned hunting rifles which are more powerful, more accurate, and capable of being magazine fed.
On the other hand if I have to read about more costumed 12-year-olds being gunned down by AK-47 fire as they hop up to trick-or-treat a well-lit house on
Halloween night, I'm going to think it's a good idea to place as many barriers as possible to limit the purchase of such weapons. Someone will probably point out that the incident I mentioned above involved an ex-felon possessing weapons illegally. Surely though, those weapons would have been much harder for him to obtain and the chance that red flags would have been raised to law enforcement would have been much greater.
Some people are arguing for a strict constructionist reading of the Constitution, but unless you're arguing weapons be limited to black powder muzzle loaders, your argument entails just as much interpretation and tailoring as anyone else's. On the other hand there were certainly creators of the constitution who were aware of the ancient Greek's use of fire weapons, so flamethrowers should be okay right?