"The study found that US Presidents exhibit elevated levels of grandiose narcissism compared with the general population, and that presidents' grandiose narcissism has been rising over time.
The relentless increases in extraversion and narcissism in US Presidents through history, which this study found, could stem, the authors speculate, from the heightened demands on political figures to be publicly charismatic and flamboyant, as media coverage gets more intense."
https://www.psychologytoday.com/blog...-does-ego-rule