All of these men were hailed as "Geniuses", and yet they presided over some of the very worst mistakes in American history.
Fool. Nobody proclaimed Lincoln a "genius" in 1860. His opponents thought of him as an uncouth backwoodsman or a small-time lawyer. Those who voted for him had to believe he was competent, but nobody claimed he was a "genius" intellectually far ahead of Douglas or Breckenridge or Buchanan. They just hoped he'd be up to the job. If people do find Lincoln particularly intelligent and eloquent now, it's perhaps because his contemporaries didn't have high expectations of him and therefore weren't disappointed. Rather, they were surprised by his capabilities.
As for the others, people want to believe the presidents they vote for know what they are doing and aren't incompetents. Democrats often look to their presidents as saviors, and as the party has grown more oriented towards college campuses and people with advanced degrees, some Democrats tend to see their presidents as geniuses. But just how many people feel that and how strongly and for how long and just how serious or significant such feelings are is harder to say.
People who thought Jimmy Carter knew what he was doing didn't think that way for long. And however smart some true believers thought Bill Clinton was, the more common impression was of slickness and cleverness, not raw intellect. In any case, such hype about candidate's intellectual powers has nothing to do with Lincoln, who certainly wasn't "hailed as a genius" by his contemporaries.
Lincoln was clearly a genius. I don't know why you even oppose this accusation against him. I've read quite a lot of his writings, and he is brilliant intellectually.
My point still stands, and it encompasses many more people than just Lincoln. Robert McNamara was considered a "Wunderkind", and he made the worst hash mess of Vietnam that it was possible to make.
History is littered with examples of people who were considered brilliant doing stupid things that no one of average intelligence would have ever considered or attempted.
There is a phrase the British use. "Too clever by half."