Dean Acheson frankly reconfirmed the right of self-preservation, when he asserted, “…law simply does not deal with … questions of ultimate power—power that comes close to the sources of sovereignty…. No law can destroy the state creating the law. The survival of states is not a matter of law”. It is beyond the law.
Given the existence of man's elementary loyalty to autonomous states, the necessity for using force springs from the need of states to depend fundamentally on self-help in order to guarantee their survival and welfare. This search for security in a system of politics without government, forces the state to be dependent upon military self-help.