With the declaration of a state of war, however, the usefulness of the Council of National Defense became instantly more obvious. The peace-time activities and interests of our people throughout the country surged toward Washington in an effort to assimilate themselves into the new scheme of things which, it was recognized, would call for widespread changes of occupation and interest. The Council of National Defense was the only national agency at all equipped to receive and direct this aroused spirit seeking appropriate modes of action, and it was admirably adapted to the task because among the members of the council were those Cabinet officers whose normal activities brought them into constant contact with all the varied peace-time activities of the people and who were, therefore, best qualified to judge the most useful opportunities in the new state of things for men and interests of which they respectively knew the normal relations. For the more specialized problems of the national defense, notably those dealing with the production of war materials, the council authorized the organization of subordinate bodies of experts, and the General Munitions Board grew naturally out of the necessities of the War and Navy Departments, which required not only the maximum production of existing munition-making industries in the country, but the creation of new capacity for production and its correlation with similar needs on the part of the foreign governments. The work done by the General Munitions Board was highly effective, but it was soon seen that its problem carried over into the field of transportation, that it was bound up with the question of priorities, and that it was itself divisible into the great and separate fields of raw material supply and the production of finished goods. With the growth of its necessary interests and the constant discovery of new relations it became necessary so to reorganize the General Munitions Board as both to enlarge its view and more definitely recognize its widespread relations. [Sidenote: The War Industries Board.] [Sidenote: Knowledge of war needs of the United States and Allies.] [Sidenote: The Council of National Defense a natural center.]