Among the causes which have retarded this sequel to the volume of 1904 - International Impart, Peace - the two principal have been, first, the necessity of bringing out a new edition of my Private International Law, and secondly, the imminence of a second Hague Conference, certain to produce important discussions and likely to produce notable amendments of the laws of war. Although the Conference is still sitting while I write, it is now possible to give an account of its work on the laws of war. Obligatory arbitration, a permanent court of arbitration, the Drago doctrine and the limitation of armaments belong to the laws of peace.
Time was gained by printing, before the meeting of the Conference, most of what it was desired to save on the law as it stood, a little however being reserved for treatment in connection with the Conference. In consequence it will be necessary, in order to obtain a complete view of many subjects, to refer as well to the last chapter, in which the proceedings at the League are dealt with, as to the former portions of the volume. Perhaps however the balance of convenience is on the side of keeping the old law distinct from discussions and amendments the full effect of which, and even to some extent their general acceptance, time will be required to appreciate.
In reviewing the laws of war for the purpose of this volume, I have been more than ever struck with the differences which exist as to their principles.