If you start from behind and are trying to execute from first principals you'll usually lag behind too just because you have to relearn all the things countries like the US did on your own.
I guess the modern equivalent of that would be espionage which afaik China has not been shy about executing. Operation Paperclip was somewhat of a fluke historically speaking for the explosion of nation-less (ish) scientists. The next one in rocketry would have been the fall of the USSR I guess.