I am the only Libertarian who thinks is not a bad idea increasing the age to 21 to own a gun?? + allowing teachers to carry a gun?

I consider myself pro-gun and I know that it is a fundamental right guaranteed by the US Constitution but I am increasingly very concerned about the recent mass shootings that are taking place in the country.

My idea is to raise arms until the age of 21 like alcohol. I have always thought that 18 is still an immature age, this allows for a reduction in attacks , i know this does not prevent the attacker from obtaining it illegally, but it can create obstacles for him.

I know there are very good 18-year-olds who want to have guns, but I don’t see anything wrong with waiting 2 years, like is not something you will die for, and today proved that the protection of the chidren is MORE important and guns constantly violate the NAP by taking innocent lives.

My other idea is to allow teachers to carry guns this can discourage possible perpetrators from trying to make a plan and a better reaction is guaranteed in any case.

What do you guys think?