One possible reason is many low hanging fruits, after WW2 with all that cheap industrial base and new technologies emerging from the war and almost no regulatio

One possible reason is many low hanging fruits, after WW2 with all that cheap industrial base and new technologies emerging from the war and almost no regulation with cold-war budgets. You could use the tech and build it fast. Check the "Secret history of Silicon Valley" by Steve Blank: https://steveblank.com/secret-history/ https://steveblank.com/secret-history/ All these are now in the mature stage. New technologies are built in China now with their large industrial base and large markets.