The Elephant in the room: all the different languages in Europe and it is only recently (past 10-20 years) that English proficiency has become high enough. Thi

The Elephant in the room: all the different languages in Europe and it is only recently (past 10-20 years) that English proficiency has become high enough. This made communication difficult and still makes it very difficult to get people to move to another country. (edit: you need to know the local language to get any kind of social life). Compare getting someone to move from Chicago to San Francisco (same language, same culture) versus getting someone to move from Norway to Italy (completely different language, very different culture). So USA had a much larger effective work force when a company wanted to hire developers and much easier marketing of the products. Europe had a lot of computer hardware companies in the 1980's but they were never able to capture the full European market. So they died out due to lack of scale. There is also the problem of every single country wanting to be a king, so there was no political will to say "we need to join forces and create one single SV" (or one single unix company). Still today EU can't create an European Silicon Valley as you don't get a SV by saying "we want a SV here", you get it by saying "everywhere else is NOT going to be a SV".