We're hardly going to ban tobacco and then turn around and legalize a product that has most of the same health risks.

Pot doesn't have the same health risks as tobacco. One would think that since pot and tobacco smoke contain many of the same chemicals, smoking pot would increase the risk of cancer. Because either even heavy pot smokers don't actually smoke as much material as cigarrette smokers or marijuana has anti-cancer properties, there is no correlation. The latter possibility is supported by research showing that cannibinoids can shrink tumor growth and kill precancerous cells.

Also of importance is that fact that it is possible to use vaporizors and cook with marijuana, taking away this risk altogether.