Sure, but how relevant or predictive of performance is IQ for the "being president" task beyond some functional baseline? The user interface for a president to

Sure, but how relevant or predictive of performance is IQ for the "being president" task beyond some functional baseline? The user interface for a president to influence the operation of a country is people and relationships. The president doesn't need to solve novel problems, they need to select the right people to identify, prioritise and solve problems (occasionally novel but probably mostly boring and universal human problems), bounded by political constraints. I guess there is also a major performance element to the role, where "thinking on feet" is very important. Probably something like "IQ" is very helpful with that.