For all the drawbacks of the USA, today it's the best place on Earth to build projects like SpaceX, period. That's the main reason to stay. Notably the foundin

For all the drawbacks of the USA, today it's the best place on Earth to build projects like SpaceX, period. That's the main reason to stay. Notably the founding father of Chinese space industry worked under von Karman in Caltech and left the USA in disappointment. However that was just one scientist in a rather different time. Today, neither Europe, nor China, nor Russia, nor India or Japan offer opportunities to develop things similar to SpaceX; I'd be quite interested in Chinese development, but would still bet against them.