Average Americans Are Stupid?
Absolutely!
You know, I don't think that's quite true -- you have to consider the fact that the majority are miseducated and indoctrinated by our so-called education-system. I mean despite the hard-core anti-american indoctrination of the past few decades (I think it became virulent/violently anti-american circa 2000) there's a lot of people who still are sensible. That proportion may be less than we'd like, and there may be a whole segment that really believes incorrect things (like "the constitution means whatever the supreme court says it does") but that is more a result of having lies and falsehoods taught to them as truths, not their "inherent stupidity".
Just watch “Watter’s World” to see Stupidity-in-Action.