The Japanese attack on Pearl Harbor on 7 December 1941 found the Corps of Engineers, like the rest of the Military Establishment, in the midst of feverish defense preparations. The Corps had been assigned the task of building up defenses in Panama, Alaska, Hawaii, and other Pacific outposts; in areas ranging from the Arctic to the tropics, engineer units were engaged in a wide variety of urgent projects. Plagued by shortages of men and materials and difficult working conditions, these defense preparations were still far from finished when the nation was plunged into war. Along with these desperate efforts to build a bulwark on many fronts, the engineers were engaged in the vital mission of creating an organization and developing equipment that would enable them to carry out their many duties on the battlefronts and behind the lines in case war broke out. By the time of Pearl Harbor much progress had been made in the relatively short time since the defense build-up began. The story of the pre-
Pearl Harbor defense preparations is one of an effort gradually getting under way from small beginnings and destined eventually to assume tremendous proportions.