What factors led to the United States' technological boom?
War and the space race.
Coming out of WW2 the U.S. was the de facto free world leader. When the Soviet Union set off its first nuclear bomb, the U.S. recognized it was in fact in an arms race. A rapid buildup in air craft and missiles funded companies like Boeing, Douglas, Republic and others to produce state of the art military air craft. In doing so, of course, these companies brought many innovations in aviation to the marketplace.
Then when the Russians launched the Sputnik satellite, the race to space was on. In the 50s and 60s the deep pockets of Uncle Sam not only kept the U.S. up with the Soviets in military and space related activities, but gave rise to innovations such as the microwave oven, GPS, digital telecommunications, among other things.