It is stupid to underestimate the power of stupidity.
I can't help thinking a huge part of the world population is stupid. That's in terms of IQ. Stupidity, like cleverness, has its benefits as well as problems. The downside of wisdom is articulated well in the Bible, Ecclesiastes 1:18:
For with much wisdom comes much sorrow, and as knowledge grows, grief increases.
We need to be fair about this. The power of intelligent people to cause havoc is huge too. Historically, I don't know which side does the most harm. Another point I would raise in defense of stupid people is that they are probably entitled to be dumb. If you're born dumb, that's the luck of the draw.