Reply: The answer is a ban. If they are not manufactured, then criminals will not have access. Putting more people in prisons is never a good answer, but at least we can agree on prosecutions for marijuana.
Catherine is wrong. It's fairly easy to make your own "assault weapon" and even a real fully automatic assault rifle. And i'll bet every firearm in my collection that the federal laws prohibiting the manufacture of a machine gun won't prevent dedicated criminals from doing so.