The promise (and premise) of international law is that of a global order based on principles, rationality and the peaceful resolution of disputes. International law insulates us from raw power, brute force, and the crude but simple — and often compelling — conclusion that might makes right. In the absence of some international police force, it is also an abstraction whose power and effect depends solely on moral authority and respect for an ideal.
Good luck with that. The idea was most famously — at least reputedly — dismissed by Soviet dictator Josef Stalin who is said to have replied to urgings to stop persecuting Catholics to win them over in the fight against Nazism with, “The pope? How many divisions does he have?”