Large nations do not have a moral right to control neighboring small countries.
They do, however, have such a right to prevent potential enemies from gaining control there.
IMO.
I agree with you that large nations do not have a moral right to control the small nations on their borders. But that is precisely what they all do in the real world, unfortunately. My argument is that we have no ability to defend an indefensible nation halfway around the world, and we should be careful about committing ourselves there.