Has America DEvolved?

I was reading an excerpt from Richard Dawkin's upcoming book, "The Greatest Show on Earth," and was floored by this disturbing fact:

"More than 40 per cent of Americans deny that humans evolved from other animals,
and think that we - and by implication all of life - were created by God within
the last 10,000 years."

Maybe I was naive to imagine that America was smarter than that. At LEAST I would have thought that, while religious, a pretty high majorty of the country at least attended a high school biology class. I was sent to 13 years of catholic schooling and I came out having learned about Darwin's theories. I don't ever actually recall being told that Intelligent Design was an option. I know ID has really taken off in the past 10 years or so, but... wow.