Historically, taxation has been the most profitable form of revenue generation. But thats no longer the case. With globalism and multi-national product creation, a single person in a nation can be many times richer than any nationstate, with technology above and beyond any nationstate. What happens when musk has electric jets and fully-reusable ICBM's, has remade the world power grid in his image, is one of few entitys even able to get to mars let alone command and control the resources of the astroid belt.