In the Air. 4. There is no code of rules of air warfare which has been formally accepted by international agreement. In the absence of such a code the actions of air forces must, basically, be regarded as conditioned by the generally accepted principles governing the conduct of war. In addition, a considerable measure of practical guidance is afforded by the Draft Hague Rules of Air Warfare drawn up in 1923. These Rules have not been formally adopted by any Government and have therefore not acquired the force of international law; moreover, they are open to criticism in certain respects.