Why doesn't the government just legalize marajuana?

It was only made illegal in the first place because hemp was a big competion for other bussneises. And apprently it made "neggros look at white women." Billions of dollars each year are wasted on the war on drugs, DEA, and locking up harmless people. Think of how much money could be saved by eliminating those wastes and by taxing marjuanna. Marjuanna is not even bad for you or addictive. It is impossiible to overdose on it and the only harmful thing is inhaling the smoke. Its still no were near as harmful as tobbaco smoke, and there are other ways to get high off of marjuanna such as brownies and using a vaporizer. So when is the government going to realize that prohibition does not work, it never has worked, and never will work.