Aside from the answers GLPers have given, marijuana induces an alternative thinking pattern.

ie. it makes you think in a different way that is way more creative and spontaneous than your normal self.

And TPTB don't want you to think about stuff other than the ones they want you to think about.

I woke up to reality because I smoke pot. It's true. It all started with me being high and watching random youtube videos, simply because everything seems more interesting when you smoke pot.

I started to watch History Channel's Ancient Astronaut series, and yeah it was fucking awesome to watch when you smoke. It soon became a habit, which later triggered me to watch a whole lot of different related videos involving conspiracies, 2012 and secret societies.

And then, even though I was high as fuck, I realized shit is getting real.

Now do you see how powerful pot is? :)