You're speculating that a US president has a relatively average intelligence - why are you assuming that? The top job in a democracy is generally one of the most competitive positions in the world and US presidents are typically exceptional in multiple different ways. It'd be really surprising to have a US president with an IQ below something like 120 and I'd personally be assuming >140 for the average. As far as I can see a 140 IQ is around the 0.1-1% mark, it isn't that rare compared to presidents (<0.01%).

> You're speculating that a US president has a relatively average intelligence - why are you assuming that

I am not assuming that: any range that has studying nuclear engineering as its floor is above average intelligence. I thought it was self-evident, but apparently not - perhaps not many people know what a "Navy Nuke officer" is. To be more explicit the range is between above average intelligence and "genius". Regardless, I will never be convinced that people with relatively average intelligence are precluded from greatness; so excuse my scepticism when fellow nerds pat themselves on the back for being the engine of the world without pointing at any research that bears this idea out.