Assault rifles have but one purpose: they are designed exclusively to commit mass murder. Hunters have no use for them, because it is against the law to slaughter a herd of deer. They are no good even for target practice, except practice to commit mass murder. The only use assault weapons can be put to is mass murder, killing many people as possible in the shortest possible time. Anyone opposing an assault weapon ban is saying: "It's OK with me that mass killings continue in this country."
Banning assault rifles should be the surest restriction to get through congress, not the most difficult. We had a ban on assault weapons when more temperate leaders ran Congress. Why was it temporary and why did we let it expire?
All guns are designed specifically to kill--animals and people. Handguns and rifles can be used for self-defense, though the Constitution is crystal clear about even these guns: they may be regulated. "In order to maintain a well-regulated militia," is the initial phrase of the second amendment, the one opponents of the assault weapon ban carefully omit in quoting that amendment.
Cars are not designed specifically to kill, but they can kill people and animals accidentally, so we carefully control cars and their owners. All cars must be registered and their owners licensed after taking a test to prove that they know (1) how to drive the car safely and (2) the rules of the road.
Why do we not control guns, the things designed specifically to kill, the way we control cars, the things not designed to kill but can accidentally? We should not only have background checks to make sure the purchaser of a gun is a "legitimate", we should register all guns in this nation and license the owners, after they have proved they know how to use them safely.