Yes, I think former President Jimmy Carter is on the spectrum.
And like any aspect of a person's personality, I think it is both a strength and a weakness of his.
Now, for persons still living, I generally prefer the approach, "A creative individual who marches to his or her own drummer. Maybe on the spectrum, maybe not. And either way is perfectly." That is, I don't want to 'out' someone ahead of their own time schedule. With presidents I think we can relax this. They are so much in the public eye, and make the decision to expose themselves to this scrunity, I think it's okay to speculate.
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And the really interesting thing, and this is an amazing coincidence of human history if true (and maybe people on the spectrum were the first people to really figure how to use television), the case can be made that both President Nixon and President Reagan were also on the spectrum.
Nixon and Carter are almost a slam dunk. Yes, they're Aspie. The really interesting case is former President Ronald Reagan. From the book The Reagans: Portrait of a Marriage by Anne Edwards, I got the idea that Ronnie was really a cerebral, intellectual guy who was very internally directed. And after he left the California governorship in January 1975, he withdrew to a cabin in the California mountains to have his alone time. From other sources, I got the idea that Nancy was his only real friend. He had loads of colleagues and supporters, but as far as actual friends, she may have been his only one.
If this theory is correct, it means from the twenty years from January 1969 to January 1989, for seventeen and a half years, the chief executive officer of the United States was a person on the spectrum. Wow.