It's a bit skewed to assume e.g. Google produces everything in the US; Google and many of those companies are multinationals, with both legal and development entities all over the world, including Europe. There's also the fact that a lot of European-based startups incorporate themselves in the US because of legal issues - it's easier to sell a US company's software in Europe than the other way around. A lot of US companies are required by law to only use US-made software, too. Probably leftovers from the Cold War.