Placed under export license July 2, 1940. Military operations would be severely handicapped if Placed under export license July 2, 1940. While importers normally carry large stocks, the opera- Up to the present time no suitable all purpose substitute for rubber has been found, and no synthetic product will answer all the purposes of natural rubber. Under this condition a war effort would be seriously impeded by a shortage of this material. At the present time a stock pile has been started, and the necessary provisions for rotation have been made. The present stock pile however will not make us self-sufficient. Steps are being taken to make up deficit by the construction of synthetic rubber plants. Critical materials are those essential to national defense, the procurement problems of which in war would be less difficult than those of strategic materials either because they have a lesser degree of essentiality or are obtainable in more adequate quantities from domestic sources; and for which some degree of conservation and distribution control will be necessary. |