My guesses, having been around psychological measuring a bit. These are only guesses, having some familiarity with IQ tests, MMPIs, taking courses in psychological test construction. And reading the biographies of most of these people.

Clinton maybe around 140, smart but more clever than smart, GHWB around 125, he's pretty good, Truman 130, Carter 135, Ford 120, smarter than he looked, Nixon 135, and also more clever than smart. Kennedy, maybe up to 135, had super advisors. FDR, Kennedy and Truman were not only bright, but actively sought the counsel of those they didn't agree with, an indicator of integrity.

Hard to tell with Reagan, there wasn't anyone home. Another front man, smarter than it seemed, but himself a pragmatic people pleaser who was run from behind the scenes. Not his own man, as GWB isn't.

GWB, I believe, was picked because he isn't very bright and is easily manipulated and controlled. Cheney is bright, as are the others behind them. Rove is, and "the women" around Bush are. And Bush is easily controlled by women. Looks for approval.

Anyway, guesses.

Arf