Yes, because all of those areas are in a covenant with each other. A Union of sorts. They've given up some measure of power to a larger federation in order to r

Yes, because all of those areas are in a covenant with each other. A Union of sorts. They've given up some measure of power to a larger federation in order to reduce their own overhead. But to be a part of that federation, they have to allow certain things. Nations could technically operate the same way, but only as part of a larger collective. There would need to be some agreed upon rules, some governing body to oversee enforcement of those rules, etc. Certain things would need to be agreed upon. What could each nation have autonomy on, what would they need to give up, what would they need to start doing, etc.