> Human rights are famously almost impossible to clearly define
Actually, not really. Just apply the "desert island" thought experiment to any given "human right." If you're not afforded that "human right" should you wind up on a desert island one day, it's not really a "human right" but rather a "right" that requires state backing to exist (and subject to its whims as you pointed out).
I must not understand this analogy, because it seems to only draw the conclusion that we are to be the objects of a totalitarian state in all cases. Taking the first fundamental right from the US constitution, the right to life, is not a given on a desert island. Any number of things, including venomous snakes and scorpions, could be your end almost immediately.
Does this mean that any given state is also justified in arbitrarily killing people on the whims of its controller?
Actually, not really. Just apply the "desert island" thought experiment to any given "human right." If you're not afforded that "human right" should you wind up on a desert island one day, it's not really a "human right" but rather a "right" that requires state backing to exist (and subject to its whims as you pointed out).