I can drive a car safely without getting road rage. I don't drive drunk. The same applies with handling guns. You trust people to drive tons of steel at insane speeds every day. You are familiar with the risk. It doesn't concern you. I suppose you would argue that government licenses offer a measure of protection, but really, that means nothing. people drive without licenses all the time. people with licenses drive poorly. Government wants to generate revenue and flex authority first and foremost, not ensure safety. A license is permission to do something that is otherwise illegal. Why has government declared so many things illegal? Because people believe in the mythology of politics, not because there was real necessity.

To my knowledge, there have been no school shootings with assault rifles in the US. None. Zero. An AR-type rifle is just a semi-automatic carbine made from modern materials. It may look like a military assault rifle, but it operates differently and has different internal components. It cannot fire multiple rounds from a single trigger press, a defining characteristic of machine guns and assault rifles. Legislating on appearances is stupid. But I also oppose the bans on machine guns, so that remains a moot point.

A handgun is very suitable for self-defense against someone with a rifle indoors. It can be carried at all times, and kept concealed until need arises. It is ideal for close range self-defense. A 9mm, .40 S&W, or .45 ACP loaded with hollow-point ammunition has ample power to reliably stop an assailant without significant risk of over-penetration endangering others. A rifle or shotgun would be preferable, but a handgun would work if they were not forbidden by law. Really, the ban on guns in schools only ensures a free fire zone for those with ill intent. And it is painfully obvious that police cannot be relied upon to aggressively respond to school shootings. The first responders are always those in the emergency.