While a duty of preparedness for war is constantly urged upon American statesmen and upon military and naval officers, the fact is too often overlooked that there is also a duty of preparedness resting upon American statesmen, jurists, and legal authors to keep abreast of the times, or even in advance of the times, in connection with rights and duties affected by war. A prominent international lawyer has written that “as the flag of a nation follows the territorial explorations of its subjects, jurisprudence follows the path of science.” This broad statement must be qualified by the admission that jurisprudence only follows at a very long distance. Too rarely do statesmen and lawyers try to visualize changing industrial, economic, social, and governmental conditions, and to promote, in advance, needful corresponding changes in the law. Especially in connection with international law and international agreements is the gift of imagination lacking, the possession of which is necessary in order to attain preparedness in any field.