See? thats exactly why i said even if they did(which as you said they seem to have done to some extent), its not really as a result of copying. industrial espionage is being carried out by all major powers in this world( thats those that have the capabilities) first of which is the U.S who has by far the largest spying/industrial espionnage capabilities on planet earth(they have been doing to us in the E.U as well, just like snowden revalations revealed, we also do it to them as well to be honest.
) no country even comes close to the U.S on this, reverse engineering(and even copying) has been done by several other powers on planet earth for ages. just like after the end of the world war II, the German Me 262 aircraft were extensively studied by the victorious allies and contributed to work on early Soviet and US jet fighters, whivh helped them tremendously in getting ahead of others. Also our engines also were licensed widely in the US. Their most famous design, the Nene also powered the USSR's jet aircraft after a technology exchange. American designs only came fully into their own until the 1960s.
So we(together with the germans) were one of the pioneers/leaders in this field.
(british flag).
So every country has to start from somewhere, it doesnt matter how you get there, as far as you get there. the end always justifies the means. After few years/decades, everybody forgets you ever relied on others/lagged behind, just like us and the U.S.