IANAL. What I would like to understand is: What supernatural being descended on earth and gave governments the supreme right to own the path from earth into space.
OK, yes, I do understand the safety argument (both in terms of danger and weaponized access to space). However, if those factors are not issues, well, why?
At a micro level it would be like having to get permission for me to drive to the beach. Or, worse, walk there.
What body of law allows government to prevent a private company from using the atmosphere to get to space?
Again, don't say "safety". That's well understood. You don't want 200 rocket companies launching at the same time from the same area. Got it. The difference is, that scenario is about traffic control and not about having to get permission to travel.
Does the atmosphere really belong to countries?
OK, so, if you could launch from a ship in the middle of the ocean you would be free to launch as you wish? Is that the case?