New Guinea Campaign (1942–44).Probably few of the 685,407 Americans sent to the Southwest Pacific Area (SWPA) through 1944 knew much about New Guinea prior to Japan's attack on Pearl Harbor—initiating the American entrance into World War II. Nevertheless, the New Guinea campaign began in summer 1942 when Japan attempted to isolate Australia through an overland attack from Buna to Port Moresby. This attack resulted in the first American action on that mountainous and jungle‐covered island. After the Australians successfully defended Port Moresby along the Kokoda Trail, U.S. forces launched an unsuccessful strike against the Japanese at Buna on the island's northern coast. Impatient with the lack of progress, Gen. Douglas MacArthur, chief of SWPA, replaced the commander, Maj. Gen. Edwin Forrest Harding, with Lt. Gen. Robert L. Eichelberger, who initially fared no better. However, MacArthur pushed Eichelberger onward, and the enemy force was finally defeated on 22 January 1943 through a grueling battle of attrition.

After the Buna campaign, MacArthur created the Sixth U.S. Army under the command of Lt. Gen. Walter Krueger. Although historians have largely overlooked Krueger's overall role in New Guinea, he coordinated the various services and developed operational plans that made MacArthur's strategy a success.

Krueger's first order was an attack on Saidor in January 1944 as part of an effort to seize the Vitiaz Strait. Next, MacArthur wanted Hansa Bay, but intercepted and decrypted Japanese Army messages (through ULTRA) tipped off SWPA leaders that the Japanese were expecting a landing there. So, he directed Krueger to seize Hollandia in April 1944. Thus began a string of amphibious assaults along the northern coast of New Guinea. Following Hollandia came Wakde and Biak in May 1944, and Noemfoor and Sansapor in July 1944. By the fall of 1944, the Sixth Army had secured New Guinea sufficiently to invade the Philippines.

Both sides invested heavily in the campaign. The Japanese committed 180,000 men, while the Allies employed five Australian divisions and six American divisions. The Americans suffered approximately 16,850 casualties and the Australians over 17,000. The Japanese lost the most, with 123,000 killed.

The New Guinea campaign was important for several reasons. It protected Australia and provided a stepladder for the liberation of the Philippines; it demonstrated the valuable role of Krueger; it illustrated the American strategy of leapfrogging, one that emphasized bypassing Japanese strongholds while capturing less defended areas; and it reflected MacArthur's obsessive desire to return to the Philippines as quickly as possible.
[See also Philippines, Liberation of the; World War II, U.S. Naval Operations in: The Pacific.]

Bibliography

Robert Ross Smith , The Approach to the Philippines, 1953.
Samuel Eliot Morison , History of United States Naval Operations in World War II. Vol. 8: New Guinea and the Marianas, March 1944–August 1944, 1962.
Ronald H. Spector , Eagle Against the Sun: The American War with Japan, 1985.
Edward J. Drea , MacArthur's ULTRA: Codebreaking and the War Against Japan, 1942–1945, 1992.
Kevin C. Holzimmer , Walter Krueger, Douglas MacArthur, and the Pacific War: The Wakde‐Sarmi Campaign as a Case Study, Journal of Military History, 59 (October 1995), pp. 661–85.
Stephen R. Taaffe , MacArthur's Jungle War: The 1944 New Guinea Campaign, 1998.

Kevin C. Holzimmer