Either you are wrong or the article's graph sourced from the US department of energy is. It shows no significant reduction, only a slight dip before a continued upward trend.

"You fly to Europe or Canada, and their security personnel have a clue - they're practical, they keep a sharp eye out, and they use the right response for the situation at hand."

The problem is that here in the U.S. we have to be oh so politically correct at all times. We have to treat 74 year old white-haired grandmothers *exactly* the same way as we treat 20-something guys with a bread and a strong middle-eastern accent when everyone knows that the odds of someone from either of these two groups doing something harmful on a flight are massively skewed towards the latter group.

The thought that humans 60 000 years ago may be smarter than us today amused me. I've not read any study on the subject and the larger brain thing is just something I've heard with a foot note that larger != better tacked on. I do suspect that an agricultural lifestyle with husbandry requires more synapses than a nomadic hunter lifestyle since wolfs, bears, etc, can manage the latter, but it would still be amusing if the OP's joke was correct in that we've gotten dumber since then (Hey, when you regularly face down grizzlies with only a stick you need smarts :).