UNITED STATES ARMY IN WORLD WAR II The War in the Pacific CAMPAIGN IN THE MARIAN AS by Philip .A. Crowl - - CENn ,R OF MIL/TAllY HfSTOfl)' UNJ71::D S7il71,S ARMY WAS/-J1NGTON, D. C., 1993 Foreword In the capture of the southern Marianas, including the recapture of Guam, during the summer of 1944, Army ground and air forces played an important, though subordinate, role to that of the Navy and its Marine Corps. Marine personnel constituted the bulk of the combat troops employed. The objective of this campaign was "to secure control of sea communications through the Central Pacific by isolating and neutralizing the Carolines and by the establish- ment of sea and air bases for operations against Japanese sea routes and long-range air attacks against the Japanese home land." Its success would pro- vide steppingstones from which the Americans could threaten further attack westward toward the Philippines, Formosa, and Japan itself, and would gain bases from which the Army Air Forces' new very long range bombers, the B-29's, could strike at Japan's heartland. Recognizing and accepting the chal- lenge, the Japanese Navy suffered heavy and irreplaceable losses in the accompanying Battle of the Philippine Sea; and the islands after capture became the base for all the massive air attacks on Japan, beginning in November 1944. In the operations described in the present volume, landings against strong opposition demonstrated the soundness of the amphibious doctrine and tech- niques evolved out of hard experience in preceding Pacific operations. Bitter inland fighting followed the landings, with Army and Marine Corps divisions engaged side by side. The author's account and corresponding Marine Corps histories of these operations provide ample opportunity to study the differences in the fighting techniques of the two services. Dr. Crowl also deals frankly with one of the best-known controversies of World War II, that of Smith versus Smith, but concludes that it was the exception to generally excellent interservice co-operation. With team effort among the military services the order of the day, this record of the Army's experience in working with the Navy and the Marine Corps should be particularly valuable both now and in the future. WARREN H. HOOVER Washington, D.C. Colonel, U.S.A. 16 March 1959 Acting Chief of Military History vii The Author Philip A. Crowl, who has an M.A. from the State University of Iowa and a Ph.D. from the Johns Hopkins University, taught History at the Johns Hopkins University and at Princeton. Commissioned in the Navy in World War II, he became a lieutenant (senior grade) and commanding officer of an LCI gunboat that was in action at Leyte Gulf, Lingayen Gulf, and Okinawa. From 1949 through 1956, Dr. Crowl was a historian with the Office, Chief of Military History. He was awarded the James V. Forrestal Fellowship for 1953-54 to study command relationships in amphibious warfare in World War II. Since 1957 he has been in Department of State Intelligence. Dr. Crowl is author of Maryland During and After the Revolution (1943) and coauthor of The U.S. Marines and Amphibious War (1951) and Seizure of the Gilberts and Marshalls (1955). viii Preface This volume is a companion piece to Seizure of the Gilberts and Marshalls by Philip A. Crowl and Edmund G. Love, also published in the Pacific subseries of the UNITED STATES ARMY IN WORLD WAR II. Together, the two volumes cover the beginning and climax (although not the conclusion) of the Central Pacific phase of the war against Japan, with special emphasis, of course, on the U.S. Army's contribution to the victories won in that area.1 Specifically, Campaign in the Marianas treats of the capture of Saipan, Tinian, and Guam in the southern Marianas; the strategic and tactical plans leading thereto; supporting operations by naval and air units; and the final development and exploitation of these islands as bases for furtherance of American joint operations against the Japanese homeland. The word joint cannot be overemphasized in connection with any considera- tion of U.S. operations in the Central Pacific. It was predominantly a U.S. Navy theater under the command of Admiral Chester W. Nimitz. The main burden of the amphibious and ground fighting in the Marianas, as in the Gilberts and Marshalls, fell on the shoulders of the U.S. Marine Corps, whose troops far outnumbered those of the U.S. Army. The author recognizes this and recognizes also that, by concentrating on the activities of the Army, this volume in a sense presents a distorted picture. The distortion is deliberate. The book represents, by definition, one segment of the history of the U.S. Army in World War II. Excellent official and semiofficial histories of U.S. Navy and U.S. Marine Corps operations in the Marianas have already been published. The present narrative of Army activities should add in some measure to what has already been written about the campaign. The reader may also gain additional insight into the nature of joint operations and interservice co-ordination. Because the number of Army troops participating in the Marianas Campaign was comparatively small, it has been possible to devote more attention here to small unit actions than in the volumes of the series that deal with the move- ments of great armies and corps over large continental land masses. In much of this narrative the spotlight centers on the infantry company. Ideally, as much attention should have been devoted to equivalent artillery units, especially since Army artillery played a major role in the Marianas Campaign. Un- fortunately, the records kept by artillery units during the campaign were—to understate the matter—terse. Unfortunately also, Army field historians who 1 The conclusion of this phase of the war is covered in Roy E. Appleman, James M. Burns, Russell A. Gugeler, and John T. Stevens, Okinawa: The Last Battle, UNITED STATES ARMY IN WORLD WAR II (Washington, 1948). ix