Pacific Blitzkrieg: World War II in the Central Pacific

Chapter 3. The Marshalls: The Perfect Operation

91 CHAPTER 3 THE MARSHALLS: The Perfect Operation W ith victories on Guadalcanal and the Gilberts, the Americans not only succeeded in wresting valuable territory from the Japanese, they also verified the basic soundness of U. S. amphibious doctrine and equipment. However, both operations also revealed a distressing number of weaknesses. With just six weeks between the Gilberts and upcoming operations in the Marshalls, there was scant time for planners to incorporate the lessons learned into training and to fix a myriad of remaining equipment issues. Still, the invasion of the Marshalls clearly demonstrated just how quickly the Americans were capable of adapting and avoiding making the same mistake twice. The operations in the Marshalls unfolded much like those in the Gilberts: two divisions, one army and one marine, conducting independent planning and training followed by parallel operations. However , in the Marshalls leaders applied many of the specific tactical and operational lessons learned in combat just weeks before. On the one side, operators had to quickly modify and upgrade equipment. On the other, planners needed to adjust the naval and artillery fire support to ensure maximum effectiveness, as well as modify landing plans to take full advantage of the increased fire support. The net result was an operation so perfectly executed that one observer remarked that “no previous battle has ever enjoyed such complete cooperation, coordination and teamwork . . . no paper maneuver could have envisioned a more powerful, smashing, successful blow to an enemy stronghold.”1 When it was over, the United States had shattered the outer ring of Japan’s strategic defense and possessed the 92 Pacific Blitzkrieg: World War II in the Central Pacific bases needed to conduct air and naval operations deep into Japanese held territory. STRATEGIC SETTING At the Casablanca Conference, the Allied leaders agreed to focus future Central Pacific operations first on the Marshall Islands and then on to the Marianas and Carolines.2 Consisting of 32 island and 867 reefs, the Marshalls cover more than 400,000 miles of the Pacific and lie just 565 miles from Tarawa. Taking the Marshalls would not only protect the Allied lines of communication and extend their control of the sea a further two thousand miles, but would also force the Japanese to divide their already stretched naval forces throughout the theater. Moreover, the Marshalls offered excellent anchorage for ships and ample space for runways.3 Unlike Guadalcanal and the Gilberts, which the Japanese seized during their prewar expansion, the Marshalls belonged to the Japanese by mandate.4 Once a German possession, the Japanese seized the islands in 1914 and after the war the League of Nations formally gave them possession of the area with one stipulation: the Japanese could not establish fortifications or military or naval bases there. However, in 1935, Japan withdrew from the League of Nations, which was, in any event, powerless to enforce the stipulation. Therefore, Japan had almost nine years to build up the defenses on the islands and used that time building airfields, naval bases, and garrisons across the atolls. The original American plan called for the simultaneous seizure of the Kwajalein, Maloelap, and Wotje atolls. These three atolls contained 65 percent of the Japanese airfields in the islands.5 The first was in the geographic center of the island group and the latter two were on the eastern edge. Follow-on operations planned on Mille and Jaluit would neutralize remaining Japanese airbases in the area. Joint planners dubbed the operation FLINTLOCK and set the invasion date for 1 January 1944, just five weeks after the anticipated completion of GALVANIC. However, by the end of October, Nimitz asked King to push the start date to 31 January, citing the need for further training, the unknown outcome of the upcoming battle in the Gilberts and the need for further photo reconnaissance. Weighing the risk of giving the The Marshalls: The Perfect Operation 93 Japanese an extra month to prepare to meet an assault against the need for adequate American training, the Joint Chiefs agreed to push the operation back, while recognizing that an unexpected setback in the Gilberts might cause a further delay.6 As the planners moved forward, Nimitz, Spruance, Turner, and Holland Smith studied the lessons coming from the Gilberts—in particular the danger of splitting the landing forces and, in turn, the naval forces, too far apart. Rather than aiming for five different atolls spread over hundreds of miles...