Dagon's points are very good. There's another aspect as well:

Tobacco import and distribution (and in some cases, production) are already nationalized in many countries, especially in the EU. National governments try to impose artificial scarcity (winding down operations, tax increases, fixed pricing), and this makes the statistics look better - officially monitored tobacco sales decrease.

Artificial scarcity cannot last: a black market of RYO tobacco, and home-made cigarettes of dubious origin is always ready to serve customer demands. In the end, the health effects of nationalizing the tobacco industry, and winding down operations, can easily be negative.