The Limits of International Law

International law is much debated and discussed, but poorly understood. Does international law matter, or do states regularly violate it with impunity? If international law is of no importance, then why do states devote so much energy to negotiating treaties and providing legal defenses for their actions? In turn, if international law does matter, why does it reflect the interests of powerful states, why does it change so often, and why are violations of international law usually not punish...