> Obviously, Yeager and the other test pilots really had “the right stuff”.
Yeager especially, since he grew up around oil field equipment and became a mechanic before a pilot, which helped with the temperamental X-1 rocket engine.
One of the advantages the US had over Japan in WW2 was that Americans in general had more education and farm equipment experience, so almost anybody could be a pilot applicant. Japan however recruited applicants at 14 yo like ninjas, and lost their “ninjas” after the Coral Sea and Midway battles. (The Axis militaries also flew their pilots until they died, whereas the US recycled them back home as instructor pilots.) Only 29 planes were shot down at Pearl Harbor, but that might be more significant than realized since the pre-war naval aviator classes only had 100 students per year, and about 10 washed out.