Trillions (billions? zillions?) of dollars in profits to the illegal market. Take away the profit incentive and the entire enterprise will collapse.
'Millions of people driving on DOPE'? Get real. We have that now. There is more danger from someone driving while taking Valium than stoned on pot.
Nobody says to legalize driving while stoned anyway. The problem of course is that there is no useful bloodtest as there is with alcohol.
But try to find some statistics about road safety where medical marijuana has been legal for a while before you go off ranting about how legalizing pot would make the roads unsafe. I think you will not find any significant increase in accidents. If there was, the first to know about it would be insurance companies who would reflect the increased risk in premiums (raising the rate for those holding a medical marijuana card).
Prostitution is only legal in a few counties of Nevada, but again it's really an issue of taking the profit away from the criminal enterprise. No pimps are necessary where it's legal. Nobody, especially not Ron Paul, is suggesting any kind of Federal regulation of prostitution. The issue was thrown here as an attack on RP's morality.

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