I can't believe how ignorant your argument is.
Yeah, so, as a contractor, I can hire drug abusers, and when they hurt themselves while working your property, if I don't have insurance, you as the property owner are liable for their medical costs and lost wadges.
Maybe the forklift operator who loaded the flatbed with block was high at the time, and left a pallet or 2 off center or a strap loose. When that pallet falls on your car and kills you, many people will be held criminally liable, but you'll still be dead.
So, what you're saying is that fine, a company can currently fire a man for coming in to work drunk, but they can't fire him if drugs are legalized and he comes to work on PCP?
The employer can set any criteria for employment he wishes.
Also....by golly damn, drugs are illegal now....but there are still people on the shop floors, including a helicopter factory I know, who've been busted by surprise drug tests and fired. So the effort to keep those evil chemicals out of the workforce has failed.
Please keep that salient and inescapable fact in mind: The War on Drugs was never winnable, was lost, and we're still spending billions and billions of dollars restricting the freedoms of EVERYONE as a result of this failure.
Lost freedoms include:
Loss of the presumption of innocence.
Inability to carry larges amounts of cash out of the country, or even around the country.
Civil forfeiture laws incentivize law enforcement agencies to bend the rules and break other laws, and have resulted in the murder of innocent citizens.
Vehicle inspections at the borders.
Citizens stopped for routine traffic violations may be held on the spot until a trained dog sniffs their vehicle, in the complete absence of any probable cause.
etc etc etc