The debate hasn't changed in 2,000 years:
"A sword never kills anybody; it is a tool in the killer's hand."
Lucius Annaeus Seneca
Every time Second Amendment issues arise two phrases are parroted, common sense gun laws & assault rifle.
The trouble with "assault rifle" is that it is invariably used incorrectly, as are the terms machine gun & automatic.
While fully automatic weapons are legal to own they are rare, expensive, and highly regulated both at the state & federal level.
When one hears news stories about AKs or ARs, machine guns or assault rifles the firearms themselves are invariably semi-automatic firearms which fire one shot each time the trigger is pulled as opposed to an automatic or "machine" gun which fires as long as the trigger is pulled, until the magazine is emptied.
When technical rules are applied using inaccurate terms what may appear common sense banning of dangerous military weapons end up banning all self-loading (semi-automatic) firearms which includes everything from pistols to shotguns, .22s to 10 gauge.
Any registration scheme becomes a defacto confiscation list when through an interpretation of a regulation formerly legal firearms are reclassified as illegal. This happened in Canada with several styles of .22 caliber rifles.
Through future administrative reclassification any firearm could be made illegal.
The major anti-gun groups if one delves deeply enough into their policies want to ban all civilian ownership of firearms.
While the focus is always on "assault" rifles (which are rarely used in criminal activity) and magazine capacity the reality is any firearm whether single shot, revolver, or break action shot gun is equally deadly on the first shot and while it seems logical to many that a 30 round magazine is more "dangerous" than a 10 round magazine the reality is it's a difference without a distinction.
Reloading a firearm with practice can be very quick & in an unarmed crowd lacking heroes like Mr. Chris Mintz or a concealed carry licensee stopping anyone with any kind of a firearm is unlikely until met with equal or greater force.
Equally one must consider the subtle but significant change to our form of government when only it or it's agents may posses firearms, which of course in the US means the connected and the rich too.
We do not have a gun problem in the US we have a sociological problem of violence, gangs, poverty, lack of opportunity, and low social mobility.
Are there people who shouldn't be allowed to own firearms?
Absolutely, but who has the right to allow what rights and liberties we have beyond the Constitution and the Bill of Rights?
"But to ban guns because criminals use them is to tell the innocent and law-abiding that their rights and liberties depend not on their own conduct, but on the conduct of the guilty and the lawless, and that the law will permit them to have only such rights and liberties as the lawless will allow. ...
For society does not control crime, ever, by forcing the law-abiding to accommodate themselves to the expected behavior of criminals. Society controls crime by forcing the criminals to accommodate themselves to the expected behavior of the law-abiding."