I will take the latter branch first. Few people have any clear ideas at present of the possibilities of air warfare. The closing years of the Great War gave the world only a very slight experience of what aerial offensives can be. Always, air operations were subsidiary to the vast surface engagements of the European belligerents; they were scouting, irritating, raiding operations; there were neither the funds nor the energy available to work them out thoroughly. In these possible overseas wars we are considering, the land armies and the big guns will not be the main factors and the air and sea forces will. The powers we have considered will therefore push their air equipment on a quite different scale; they will be bound to deliver their chief blows with it; we may certainly reckon on the biggest long-range airplanes possible, on the largest bombs and the deadliest contents for them. We may certainly reckon that, within three or four hours of a declaration of war between France and England, huge bombs of high explosive, or poison gas, or incendiary stuff, will have got through the always ineffectual barrage and be livening up the streets of Paris and London. Because it is the peculiarity of air warfare that there are no _fronts_ and no effectual parries. You bomb the other fellow almost anywhere, and similarly he bombs you. Many people seem to think that America and Japan are too far from each other for this sort of thing, but I believe there is nothing insurmountable in these distances for an air offensive. It will be a question of days instead of hours, that is all, before the babies of Tokio or San Francisco get their whiffs of the last thing in gas. The job will be a little more elaborate; it will involve getting the air material to a convenient distance from the desired objective by means of a submersible cruiser; that is all the difference.