Today in 1945, the US invasion of Iwo Jima began. During the next 35 days, tens of thousands of American Marines and the island’s Japanese defenders would be killed or injured. It is remembered today as one of the most costly battles of the Second World War.
Iwo Jima is an eight square mile volcanic island located approximately 650 miles south of Tokyo in the Japanese Volcano Islands Chain. Its main defining feature is Mount Suribachi, a dormant vent 546 feet high. The rest of the island is relatively flat and comprised of volcanic ash, a substance that would create challenges for the invading Marines. In 1945, there were two airfields on the islands with another one under construction.
War planners in Washington called for an invasion of the island for several reasons. First, its location allowed the Japanese radar operators stationed there to warn Tokyo of incoming American bombers. Second, the captured island could be a forward airbase for P-51 Mustangs, which could then escort B-29 Superfortresses on their missions over Japan. Finally, Iwo Jima would act as a rescue and repair station for bombers too damaged to return to their bases in the Mariana Islands.
And so at 2AM on the morning of February 19th, 1945, the thunder of 14- and 16- inch guns belonging to the battleships of the United States Navy marked the beginning of the invasion of Iwo Jima. The naval bombardment was followed by a heavy bomber raid, then more shelling from offshore. Military planners believed this “softening up” operation would be sufficient, as the island was believed to be lightly defended. Nothing could be further from the truth.
Lieutenant General Tadamichi Kuribayashi, the Japanese general in charge of Iwo Jima’s defense, had come to the island in 1944 with the intention of turning it into an impregnable fortress. After evacuating the civilian population, he ordered tunnels built everywhere on the island connecting hidden artillery positions, sniper hideouts, and pillboxes. Mt. Suribachi, crisscrossed with tunnels, was home to many artillery pieces, some hidden behind steel doors. Unlike most previous invasions where the Japanese troops met their enemy on the beaches, Kuribayashi ordered his men to garrison defensive positions inland and put up no resistance to the Marines wading ashore.
Despite these measures, Kuribayashi knew that he and his men would never leave Iwo Jima. By early 1945, the Imperial Japanese Navy had ceased to be an effective fighting force and the nation’s merchant fleet was in shambles. While the Air Force was still able to marshal a defense of the home islands, her planes were generally too short-ranged to defend Iwo Jima. The 80 interceptors once stationed on the island had all been destroyed either in combat or by the incessant American bombing raids of the previous year. The 21,000 Japanese defenders were alone with no chance of evacuation, resupply or victory. Their only hope was to make an invasion so costly that the Allies would be forced to reconsider their plans to invade Japan.
The first wave of the 30,000 Marines of the Fifth Amphibious Corps landed at 9AM on the morning of the invasion. The lack of resistance on the beach made many think the pre-invasion hammering of the island had killed its defenders. That changed when the lead Marines reached the first line of concealed Japanese bunkers. Machine guns opened up on them at point-blank range while the artillery hidden on Mount Suribachi rained down shells. What was thought to be a lightly-defended high spot in the ocean was quickly turning into a living hell.
Heavy naval artillery, air support, the arrival of tanks and the courage of the individual Marine allowed them to slowly advance inland. By nightfall of the first day, Suribachi was cut off from the rest of the island, at least above ground. The Marines now knew about the underground defense network and expected a bloody battle for the summit of the mount. But while small numbers of Japanese did attack the men tasked with taking the hill, resistance was light. Thus, by February 23rd, the US controlled the summit. That day, one of the most famous pictures of the 20th century was taken as a group of Marines and one Navy corpsman raised an American flag on top of Mount Suribachi. It was actually the second flag to be raised there, but that’s a story for another time.
Despite the morale boost of the flag-raising on Suribachi, the battle for Iwo Jima was far from over. The tunnel system allowed Japanese soldiers to turn up almost anywhere, even in areas that had been considered securely in American hands. The Marines quickly learned that small arms fire did little to roust their enemy from his underground positions; instead, the grisly work was mostly accomplished with hand grenades and flamethrowers. Most of the Japanese attacks began taking place at night and some were only repelled after fierce hand-to-hand combat. Tales of courage and self-sacrifice during the 35-day effort are more numerous than can be recounted here; as Navy Admiral Chester Nimitz said of the Americans who fought on Iwo Jima, “Uncommon valor was a common virtue.” One quarter of the Medals of Honor given to Marines during the Second World War were awarded for actions on Iwo Jima. Five more went to sailors, all but one of them corpsmen.
On March 26th, 1945, Iwo Jima was declared secure. Of the 21,000 Japanese defenders, approximately 20,700 of them died while only 216 were captured. The Americans fared worse in terms of casualties: nearly 28,000 men were either killed or wounded, greater than the total number of Allied casualties incurred during the D-Day landings in France in June, 1944. A number of Japanese soldiers continued to live in the tunnels, coming out at night to scavenge for food. They surrendered one by one, but the last holdout lived underground on the island until 1951.
It wasn’t long after the invasion of Iwo Jima that some in the United States began to question the strategic importance of the island. The plan to use the captured airfields as a base for fighter escorts came to almost nothing, as only ten escort missions were flown from there. The Japanese early warning radar network continued to operate even after the Iwo Jima invasion, as the island of Rota in the Mariana chain continued to function as an early warning post and was never invaded.
The island WAS very useful as an emergency airstrip for B-29s returning from missions over Japan. Between March, 1945 and the end of the war in August of that year, 2,251 Superfortresses landed on Iwo Jima. The first one, on March 5th, landed while fighting was still taking place near the airstrip. Doubtless many lives were saved because of the availability of those facilities. It is also important to remember than in early 1945, war planners were still imagining an invasion of the Japanese home islands and a war lasting until 1947. Iwo Jima would have been one of the staging areas for aircraft taking part in the invasion.
The debate over the wisdom of the costly invasion of Iwo Jima will probably continue for generations. It is worth remembering, however, that we have the luxury of history on our side, something that the men making the decisions during the war did not.