The United States has the highest incarceration rate in the world. If drugs were legalized they'd start arresting us for something else. It has nothing to do with the crime rate.
https://en.wikipedia.org/wiki/Incarceration#Incarceration_ra...
https://en.wikipedia.org/wiki/Incarceration#Incarceration_ra...
Just getting 3 Strikes laws undone would be practically impossible. Any politician proposing it would immediately come under attack by an opponent who would gladly pick up that rock. Political courage is uncommon enough to be an oxymoron.
But there are a whole lot of people in the pen for selling relatively small amounts of drugs. I don't see the government passing new laws to replace them if drug laws were repealed.
Graphical evidence that the war on drugs specifically is the problem: http://upload.wikimedia.org/wikipedia/commons/e/e2/US_incarc...