"Beer impairs driving ability, will you campaign to bring back prohibition too?"
Driving will impaired by alcohol is against the law, the analogy is a little flawed. And it is an issue for government. Medical doctors do not police the streets, police officers do. A doctor can tell a patient till they are blue in the face, but a doctor cannot force a person to do what they say....police officers can and do.
Sorry, but I am against legalization of drugs period.
Apparently you are against legalization of safe, non invasive medical drugs. This kind of dogmatic, unreasoned policy making will not get you elected.
DWI is against the law, regardless of the substance.