It's no different than a nail gun, chainsaw, or any other tool you can hurt yourself with. If you are going to use one, you better make sure you're trained to do so.
I don't think it's similar at all. Nail guns (at least here in New Zealand) only fire if the muzzle is forced against something hard - you can't accidentally discharge one by pointing it across the room at someone. Nail guns, even if they do injure someone, are far less likely to actually kill them. Chainsaws are much harder to use than a firearm. A child playing with a firearm can easily kill themself. A child playing with a chainsaw is unlikely to be able to start it.
Finally, people do not carry nail guns or chainsaws on their person or have them sitting under their pillow for the purpose of using them against a threat. I have no problem with people owning firearms at all. It's having them ready to use and easily accessible that I don't find sensible.
I have exactly as much sympathy for someone shooting themselves with their own gun as I do for someone getting shot because they broke into the home of a gun owner... none. It takes about two days of proper training to never pick up a gun in a way that will make it go off before you want it to.
So if your three year old child got hold of your readily accessible firearm and shot themself, they deserved it right?
A drunk or untrained driver behind the wheel of a car is a danger to himself and everyone around him. A drunk or untrained gun owner playing with his firearm is in the exact same situation. That doesn't mean we should all go back to riding horses or give up our guns.
This is back to the same "we should ban cars too" fallacy. I do not advocate the banning of firearms. Absolutely not. Motor vehicles are
controlled and motor vehicle users are
controlled. They are controlled by registration, licensing, and rules. Failure to meet the standards of these results in a loss of right to operate or own a motor vehicle.
In contrasts the same level of control is not universally adopted for firearms and firearms users. However if we look at the statistics:
About 44,900 people are killed every year in the USA by motor vehicles (this includes all types of motor vehicles including trains, boats, aircraft, etc). About 19,000 occupants of cars, pickups, and vans are killed every year.
About 28,000 people are killed every year in the USA by firearms. 16,000 are killed by self harm using a firearm, 11,000 by assault using a firearm, 300 by legal intervention with a firearm, 200 by discharge of a firearm of unknown cause, and 600 by accidental discharge of a firearm.
There's about 240 million registered land passenger motor vehicles in the USA (this does not include things like motorbikes or air and water motor vehicles) and about 200 million licensed drivers. The overwhelming majority of US households own at least one car, with an average of 2.6 per household.
In contrast, only 1/4 of American adults (about 54 million people) own firearms (total numbers of firearms are not known but thought to be around 200 million) and of those about 50% are not stored locked up, and about 16% are stored unlocked and loaded. (This is important because I have no issue with gun ownership in itself, only how they are stored and used).
The average American also spends a far, far greater percentage of their time in a motor vehicle than they do in possession of a firearm.
So from that we can conclude that firearms are
at least comparably as dangerous as motor vehicles (and far, far less useful a tool). So why are motor vehicles so rigorously controlled, and firearms are not? It makes no sense to me.