I got nothing against Americans myself.
But pretty much I don't see your country as not too bright, and I'll provide a couple of examples:
1. The common you don't now where Australia is on the map. Ahh how many sketchs have I seen on that.
2. You only learn about YOUR history duing your primary and most of your secondary years
3. Your military tatics-Shoot first ask questions later
4. The New Orleans incident how the place turned into "mob rules" if I may
5. I don't know if this is still going on over there or if it actually happened, that you had guns and other dangerous weapons in your hardware stores for SALE!.
6. Look who your president is.

EDIT:
7. You can be the most self-centred people