The First World War and the decades of turmoil thereafter, namely the 1930s, the Second World War and, later, the Cold War, are historical moments relevant to prove that one of the most famous ideas of International Relations is, in fact, impossible. The idea of an ontologically, yet not phenomenologically, permanent state of war is incompatible with a world filled with sovereignties. These sovereignties have never lost their political and strategic control of wars, not even in the main conflicts of the 20thc. All these conflicts were strategically mediated and never led to absolute war.