So, why hasn't that been done the last 200+ years? Corrupt politicians? Evil NRA? Or the majority of people simply do not want guns taken?
Inertia.
It is one of the most powerful non-forces in the world.
Combined with rich business interests, the average, sane guy has no chance. When your only reprentatives are already bought by those powers, what are you gonna do? Maybe blow up gun shops?
Just like the drug problem: why isn't it fixed? Because too many people enjoy the drugs, depend on them, make a lot of money by selling them and preventing their supply from getting stopped.
Just this week, here in Mallorca, a 28-year-old woman already with record of using and dealing, stoned, drove her car into a group of cyclists putting one into a coffin and several others on critical lists. This out in the sticks in Capdepera, near Arta and Cala Ratjada. Ask yourself: how come she was still free, able to drive her wheels instead of being in some prison or mental hospital?
Regarding the knife and acid attacks: yes, there are crazies out there, congenital idiots who must never be called idiots, but simply "disadvantaged young people" with no blame or responsibility for themselves and their actions at all. It's obviously the fault of the "government" for failing to give them a free pass to a great life.
Instead of bulding new highways in the north, to service non-extant industries, they should save a lot of money and time by building new jails.