Why are cigarettes legal, but marijuana illegal?

[ArtMonkDrillz]

I have a hard time believing that pot could be made widely available in any one state, even if it was legalized there, because it is still considered a federal crime to possess/smoke it. IN place like California, for instance, it is legal for medical purposes but you still have to keep it (and the shops that sell it) on the down low because the Feds are constantly looking for doctors who prescribe it for their patients so they can bust them.
I feel like the same thing would happen in Nevada. The local and state cops would ignore it but the whole state would be crawling with DEA agents.