This may have seemed like a crazy question to ask 50 years ago, but now I think it's a legitimate one to ponder...
Would you even want to be President?
The American President used to be viewed with universal reverence and respect, even by those who did not agree politically. Little kids thought that becoming President was a cool dream. You'd be "the most powerful person in the world" and everyone would look up to you. You'd help shape history, and if you were any good at it, you'd truly become PART of history.
These days, the President's every move is closely scrutinized, sometimes to ridiculous lengths thanks to the 24/7 news cycle. If you do something "normal" people do all the time, like take a family vacation or have a beer at a sporting event, you're raked over the coals. Regarding job performance, you're expected to perform miracles and do everything you want to do even though you're really not as powerful as many think, given how partisanship rules. Physically and mentally, it's an incredibly taxing position. Just look at how quickly recent Presidents have aged while in office.
I don't want anyone to think this specifically about Barack Obama in any way, because this is something I've talked about with friends since when George W Bush was in office. Take Obama and Bush and every other recent individual out of the equation, and just look at the position in general.
If you were offered the Presidency today, would you even want to take the job?