The AR is NOT "high power" and there are dozens of other semiautomatic rifles that fire the same round.
Maybe you should read the article by the doctor who treated the wounded at Parkland.
The one girl whose liver was completely obliterated by a M-16 round.
the AR-15 fires the same round as the M16, designed to inflict maximum damage on an enemy soldier.
And your liability laws are ridiculous unless you hold every single manufacturer of every single product to the same standard which means people can sue Distilleries because a drunk driver killed someone, or sue Louisville Slugger because someone got his head caved in with a bat etc. It doesn't fly and never will
Actually, it flew just fine. After the DC snipers, a jury found that the gun store that gave them the guns (one was a felon, the other a minor) and the manufacturer were irresponsible in the way they were selling guns.
Then the NRA, realizing they could have a situation like the tobacco industry did, got Congress to pass a widespread immunity for them that other industries don't enjoy.
Unlike baseball bats or booze, guns are DESIGNED TO KILL PEOPLE. Particularly assault rifles, which were designed as weapons of war.