In 35 years I have never seen one heavy pot smoker get "man boobs."
...give you cancer and other lung diseases, ...
There is no peer reviewed evidence of that. As I sit here puffing on a Macanudo I realize it is my choice how to live my life. No one else's.
...you give off second-hand smoke, ...
Oh geeze! Not that nico-nazi horse crap for pot too? Never proved for tobacco and who is going to be exposed to second hand pot smoke that hasn't chosen to be there?
...it causes lethargy, can cause mild paranoia or erratic behavior, may cause hallucinations, ...
It can if you let it. Its effects are pretty much overcome by even a little willpower.
...and reduces physical dexterity (e.g. reduced reaction time while driving).
Actually there was a study done in Britain that showed people who had smoked pot drove better.
I'd like to see a credible study that proves pot improves coordination in the average person. HA!
Back in college, I'd shoot my best pool with 2 beers. But, I know my coordination drops off precipitously after a few more (no one who drinks believes this of them self - they're always smarter, funnier, a better driver, etc. after more drink). I could still run the tables since I was quite a bit better then average. That didn't mean my performance was enhanced by booze, it just didn't degrade my level down to average.
As for second hand smoke, if pot was legalized just like cigarettes, of course people would be subjected to it without consent (esp kids of smoking parents). My body can't handle being around smoke anymore and I'm damn glad that the smoking Nazis have made it illegal to light up in most public places. No one has the right to make me sick just because I want to grab a bite to eat somewhere besides my own kitchen.