The penultimate test of U.S. Marine Corps amphibious doctrine and practice. By the end of 1944, American forces had secured from Japan control of the Mariana Islands to provide air bases for B-29 strategic bombers that could strike Japan. En route to Japan, these bombers flew over Iwo Jima (Sulphur Island). Located in the Japanese Bonin Islands, halfway between the Marianas and Japan, the pork-chop-shaped volcanic island of Iwo Jima is from 800 yards to 2.5 miles wide and 5 miles long, with a total area of some 8 square miles.
Iwo Jima housed a large radar facility that gave Tokyo advance notice of impending air attacks, as well as three airstrips for fighter aircraft used to harass the U.S. bombers. As a consequence, U.S. commanders formulated Operation DETACHMENT to seize Iwo Jima. In American hands, the island's airstrips would provide emergency landing facilities for bombers returning from Japan and also allow U.S. fighters stationed there to escort bombers the entire length of their missions.
Japanese leaders realized the strategic importance of Iwo Jima and began reinforcing it a year prior to the American invasion. Lieutenant General Kuribayashi Tadamichi, the island's commander, disregarded the traditional Japanese defensive doctrine of meeting the enemy at the shoreline and implemented a new strategy that relied on 1,500 interlocking strong points inland, designed for a battle of attrition. His force of 21,000 men dug out thousands of yards of tunnels in the soft volcanic rock to connect natural caves, underground bunkers, and man-made "spider-traps" from which concealed defenders could infiltrate and attack any enemy positions. These extensive subterranean complexes would also shield the defenders from extensive preliminary air and naval bombardment by U.S. forces. Japanese artillerymen also preregistered the beachheads to maximize the effectiveness of their own shelling. Kuribayashi ordered the defenders to die in place and to kill at least 10 Americans before dying themselves. He was, however, handicapped by a lack of freshwater. The absence of a natural harbor limited Japanese reinforcement of the island, and U.S. submarines also sank a number of Japanese supply ships, including one transport with a regiment of Japanese tanks.
Beginning in August 1944, U.S. Army aircraft in the Marianas subjected Iwo Jima to air strikes, and from 8 December, the island came under daily attack. Three heavy cruisers bombarded Iwo Jima three times in December and twice in January. Then, for two weeks beginning in late January, Seventh Air Force bombed Iwo Jima day and night, and B-29s struck it twice. In all, U.S. forces dropped 6,800 tons of bombs and fired 22,000 rounds of 5-inch to 16-inch shells prior to the invasion, the heaviest bombardment of the Pacific war. Still, the naval bombardment of the island, begun on 16 February 1945, lasted only three days, a far shorter period than V Marine Amphibious Corps commander Lieutenant General Holland M. "Howlin' Mad" Smith had requested. Smith led a force of 80,000 men, supported by Admiral Raymond A. Spruance's Fifth Fleet. Vice Admiral Richmond Kelly Turner had overall charge of the invasion.
On 19 February 1945, 30,000 U.S. Marines from the 3rd, 4th, and 5th Marine Divisions stormed ashore, only to encounter Iwo Jima's coarse, black volcanic sand. Heavy surf smashed the landing craft against the island's shelf, and the deep sand immobilized many vehicles on the beach. The resulting logjam of men and equipment on the beachhead provided prime targets for highly accurate Japanese artillery fire. With little or no cover, the Marines had no choice but to fight their way inland. One group wheeled south, toward the island's most prominent terrain feature, the 556-foot Mount Suribachi, while the majority of the Marines attacked northward toward the first airfield. On D+4 (the fourth day after the initial landing), Marines reached the crest of Mount Suribachi, and although still under fire, they raised a small American flag. A few hours later, another group raised a second, larger flag as Associated Press reporter Joe Rosenthal impulsively snapped a photo. Rosenthal's picture of these five Marines and one navy corpsman planting the second flag became a Marine Corps icon and the symbol for American victory in the Pacific. The photograph remains one of the most widely reproduced images of all time.
Marines assaulting the main line of resistance to the north waded through rain-soaked sand into a maze of Japanese pillboxes, bunkers, and caves. Assisted by flamethrowers, demolition charges, bazookas, tanks, and air support, they pushed their way through Kuribayashi's defenses for 36 days, sometimes advancing only a few feet per day. By 26 March 1945, nearly 70,000 Marines had conquered most of the island, at a cost of approximately 6,500 dead and 20,000 wounded. More than 95 percent of the Japanese defenders died during the same period, and pockets of Japanese resistance continued to emerge from concealed cave complexes throughout April and May, resulting in 1,600 additional Japanese deaths. Fewer than 300 Japanese were taken prisoner.
Was the capture of Iwo Jima worth the high cost? With the island firmly in U.S. possession, U.S. bombers pounded the Japanese homeland unabated. In the midst of the heaviest fighting on 4 March, the first of 2,500 U.S. bombers made emergency landings on the island, and some 2,000 B-29s force-landed there from March to August. Given that these planes carried 10-man crews, this represented up to 20,000 airmen. The U.S. Army Air Forces (USAAF) VII Fighter Command moved to Iwo Jima and began to send its long-range P-47 Thunderbolts and P-51 Mustangs as escorts with the B-29s to Japan. The bombers now mixed medium-level daytime raids with the low-level night attacks. With the USAAF fighters along, losses of Japanese planes mounted rapidly, while those of the B-29s continued to decline.
The struggle for Iwo Jima epitomized the courage and esprit of the Marine Corps during the war. Twenty-two Marines, four navy corpsmen, and one navy officer on Iwo Jima earned the Medal of Honor (almost half of them posthumously), accounting for one-third of all such medals won by Marines during the entire war. Fleet Admiral Chester Nimitz testified to the level of courage and bravery among the Americans fighting on Iwo Jima in stating, "Among the Americans who served on Iwo Jima, uncommon valor was a common virtue."
Derek W. Frisby
Alexander, Joseph. Closing In: Marines in the Seizure of Iwo Jima
. Washington, DC: History and Museums Division, Headquarters, U.S. Marine Corps, 1994.
Bradley, James. Flags of Our Fathers
. New York: Bantam Books, 2000.
Wright, Derrick. The Battle for Iwo Jima, 1945
. Phoenix Mill, UK: Sutton Publishing, 1999.
Tucker, Dr. Spencer C.; Roberts, Dr. Priscilla Mary. Encyclopedia of World War II: A Political, Social, and Military History (Santa Barbara, CA: ABC-CLIO. 2005).