As you can see, the moderation converged on a more proper +5 Insightful
I've read the post carefully and it doesn't qualify as Flamebait IMHO. It states a controversial political opinion and thus invites a discussion, which may lead to flamage, but does not itself lead with a flame.
So this looks like someone who doesn't like the position trying to suppress it, by hitting it with the most plausible -1, in the hope that one more like-minded person will have mod points and get it suppressed before very many people see it. That works for "politically incorrect" subjects (such as criticisms of the "heat death of the Earth, everybody panic and suppress technology" interpretation of climate data), where a crowd of like-minded free speech haters are ready to suppress opposing opinions. But pro-pot doesn't appear to attract that much system-gaming opposition.
Right now it only takes two downmods to hide a non-anonymous itme. It seems to me that we have enough people willing to moderate that it's time to scale up the mod system, so a small astroturf operation can't shut down debate. Say: double it: Mods get 10 points, -2 hides, non-anynomous starts at +2, high-karma at +4, doulble everybody's current karma and readjust the cutpoints for bonuses, caps, and the like. That would mean it would take two moderators to suppress a anonymous post and four for authors willing to risk reputation. (It would also mean more work for those who are willing to moderate - but they might be more willing to spend a point if they had more to spend.)