I question the meaning of saying if civs kill each other then it's a dangerous world out there which is inherently circular. I question power and visibility be

I question the meaning of saying if civs kill each other then it's a dangerous world out there which is inherently circular. I question power and visibility being independent variables. I question the idea of needing to be more powerful to destroy each other when a weaker society could still kill the other simply by attacking first. A kinetic care package could spend as little as 7 hours inside Pluto's orbit and it wouldn't have to be mountain sized. It might indeed only follow it's own light by a small increment leaving even a much more advanced tech with few options. Overall entirely pointless.