So what?
Makes no sense a teacher can’t arm themselves.
Makes no sense that the amount of bullets in a gun don’t mean nothing.
5 bullets..30...100. It makes no difference what makes a difference is the people. Damage can be done with a single bullet no matter the amount used. It’s not the guns it’s the people.

Don’t blame it on the instruments blame it on the person wielding it. A gun is just an inanimate object.. it only does something when a human is involved. Just like you said “I can go online and buy” don’t blame the guns blame those who are not fit to own one.