Please answer two questions so I can hopefully become less dense.
Why are some "inherently dangerous" items restricted?
When does an item cross a line in where we consider the item to be "inherently dangerous" and this worthy of restriction?
Are you really not sure why inherently dangerous items are restricted? Really? Cars are inherently dangerous; they are big and heavy and move fast. They are also really useful in committing crimes. So their use is restricted to those who have a licensed sober. They are required to be registered as well.
Guns are made specifically to end life, whether human or otherwise. They are clearly dangerous. This is not a controversial statement at all. Much of what gun rights activists use to justify their ownership of guns is specifically
because they are so effective at killing (the whole people vs. government scenario).
The greater point I'm making here, that so many gun rights folks completely ignore, is that what dangerous items are worth regulating and to what degree is an open question; it's a matter of choice what kind of risk is worth the reward.
Which mass shootings have been committed with an automatic weapon?
I only know of one such instance and it wasn't truly a mass shooting, that's the North Hollywood bank robbery.
Thankfully automatic weapons
are regulated to a decent degree which makes them expensive and relatively rare. I would argue that's a wise choice and something to continue enforcing.
The more common issue with mass shootings is compact semi-auto weapons with large magazines. It's not clear that the risks of having these relatively easy to acquire outweigh the benefits, since they aren't ideal for legitimate uses. Hunting is best done with long arms and self defense is easily secured with pistols and shotguns. Large capacity magazines offer little benefit here as well.
1) Because they are terrific defensive tools and excellent sporting equipment given they are used in their intended manner.
Self-defense situations in which a pistol or shotgun wouldn't cut it basically don't exist. Sporting purposes aren't worth a single life as far as I'm concerned. The kind of additional damage these weapons deal in shooting sprees isn't worth whatever marginal advantage they serve for the extremely rare case of, say, and entire platoon trying to invade your home.
2) Because making them illegal does not make them unavailable.
The idea is to make the less available. That's what bans and regulations do in effect. Simply because it will always be possible for some sufficiently wealthy people to secure an item doesn't mean it makes any sense to legalize it. It's also possible to secure wildly toxic chemicals like osmium, but there are very good reasons to keep certain items and materials difficult to acquire.
Because nothing other than guns can damage large numbers of people -
News from The Associated Press
That isn't a reason to legalize or deregulate other dangerous items. Bombs also kill a lot of people, and yet, guns still do as well. We're taking about guns, though, not bombs or knives.
Spouting off facts would suit you more, is that a fair assumption?
Facts are necessary to determine what risks are worth taking, yes. It can't be decided through ideology or assumption. Again, the greater point is that what risks are and aren't worth taking is a matter of choice. You need to make a coherent argument, supported by facts, reason etc. that it's better to have guns, or specific guns, readily and cheaply available.
(For the record I'm a gun owner and don't think a universal ban on guns is worth the cost, but there are actual arguments for this that gun rights activists so rarely bother making, instead preferring to make insipid hyperbolic arguments like yours.)