Battle of Iwo Jima

The Battle of Iwo Jima (19 February – 26 March 1945) was a major battle in which the United States Marine Corps (USMC) and United States Navy (USN) landed on and eventually captured the island of Iwo Jima from the Imperial Japanese Army (IJA) during World War II. The American invasion, designated Operation Detachment, had the goal of capturing the island with its two airfields: South Field and Central Field.
The Japanese Army positions on the island were heavily fortified, with a dense network of bunkers, hidden artillery positions, and 18 km (11 mi) of tunnels. The American ground forces were supported by extensive naval artillery, and enjoyed complete air supremacy provided by U.S. Navy and Marine Corps aviators throughout the battle. The five-week battle saw some of the fiercest and bloodiest fighting of the Pacific War.
Unique among Pacific War battles involving amphibious island landings, total American casualties exceeded those of the Japanese, with a ratio of three American casualties for every two Japanese. Of the 21,000 Japanese soldiers on Iwo Jima at the beginning of the battle, only 216 were taken prisoner, some of whom were only captured because they had been knocked unconscious or otherwise disabled. Most of the remainder were killed in action, but it has been estimated that as many as 3,000 continued to resist within various cave systems on the island after most major fighting ended, until they eventually succumbed to their injuries or surrendered weeks later.
The invasion of Iwo Jima was controversial, with retired Chief of Naval Operations William V. Pratt stating that the island was useless to the Army as a staging base and useless to the Navy as a fleet base. The Japanese continued to maintain early-warning radar capabilities on Rota island, which was never invaded by American forces. Experiences with previous Pacific island battles suggested that the island would be well-defended and that seizing it would result in significant casualties. The lessons learned on Iwo Jima served as guidelines for American forces in the Battle of Okinawa two months later, as well as for the planned invasion of the Japanese homeland.
Joe Rosenthal's Associated Press photograph of the raising of the U.S. flag at the summit of the 169 m (554 ft) Mount Suribachi by six U.S. Marines became a famous image of the battle and the American war effort in the Pacific.
After the American capture of the Marshall Islands and the air attacks against the Japanese fortress island of Truk Atoll in the Carolines in January 1944, Japanese military leaders reevaluated their strategic position. All indications pointed to an American drive toward the Mariana Islands and the Carolines. To counter such an offensive, the IJA and the Imperial Japanese Navy (IJN) established an inner line of defenses extending generally northward from the Carolines to the Marianas, from there to Japan via the Volcano Islands, and westward from the Marianas via the Carolines and the Palau Islands to the Philippines.
In March 1944, the Japanese 31st Army, commanded by General Hideyoshi Obata, was activated to garrison this inner line. (Note that an army-sized unit in Imperial Japanese military doctrine was about the size of an American, British Army, or Canadian Army corps. The Japanese Army had many armies, but the U.S. Army had only ten at its peak, with the 4th Army, the 6th Army, the 8th Army, and the 10th Army being in the Pacific Theater. The 10th Army only saw action at the end of the Pacific war, landing on Okinawa in the spring of 1945.)
The commander of the Japanese garrison on Chichi Jima was placed nominally in command of IJA and IJN units in the Volcano Islands. After the American conquest of the Marianas, daily bomber raids from the Marianas began to hit mainland Japan as part of Operation Scavenger. Iwo Jima served as an early warning station that radioed reports of incoming bombers back to the Home Islands, allowing Japanese air defenses to prepare for the arrival of American bombers.
After the U.S. seized bases in the Marshall Islands in the battles of Kwajalein and Eniwetok in February 1944, Japanese reinforcements were sent to Iwo Jima: 500 men from the naval base at Yokosuka and 500 from Chichi Jima reached Iwo Jima during March and April 1944. At the same time, with reinforcements arriving from Chichi Jima and the Japanese home islands, the army garrison on Iwo Jima reached a strength of more than 5,000 men. The loss of the Marianas during the summer of 1944 greatly increased the importance of the Volcano Islands for the Japanese, who were concerned that the loss of those islands would further facilitate American air raids against the Home Islands, disrupt war manufacturing, and severely damage civilian morale.
The final Japanese plans for the defense of the Volcano Islands were hamstrung by several factors:
In a postwar study, Japanese staff officers described the strategy used in the defense of Iwo Jima in the following terms:
After the Battle of Leyte in the Philippines, the Allies were left with a two-month lull in their offensive operations before the planned invasion of Okinawa. Iwo Jima was considered strategically important since it provided an air base for Japanese fighter planes to intercept long-range B-29 Superfortress bombers flying to strike targets in Japan. In addition, it was used by the Japanese to stage intermittent air attacks on the Mariana Islands from November 1944 to January 1945. The capture of Iwo Jima would eliminate those problems. The island's airfield would also support P-51 Mustang fighters, which could escort and protect bombers en route to Japan.
American intelligence sources were confident that Iwo Jima would fall in one week. In light of optimistic intelligence reports, the decision was made to invade Iwo Jima, and the operation was codenamed Operation Detachment.
In June 1944, Lieutenant General Tadamichi Kuribayashi was assigned to command the defense of Iwo Jima. Kuribayashi knew that if the Americans decided to land on Iwo Jima, his garrison could not win the battle, but he hoped to inflict massive casualties on the American forces so that the United States, and its Australian and British allies, might reconsider carrying out an invasion of the Japanese home islands.
Drawing inspiration from Japanese defensive tactics used in the Battle of Peleliu, Kuribayashi designed a defensive strategy that broke with traditional Japanese military doctrine. Rather than establishing his defenses on the beach to contest the landings directly, he instead opted for defenses in depth. Kuribayashi's troops constructed a complex system of mutually-supporting fortifications, often linked together by a vast tunnel system, equipped with heavy machine guns and artillery. Takeichi Nishi's armored tanks were camouflaged and utilized as static artillery positions. Because the tunnel linking Mount Suribachi to the rest of the island was never completed, Kuribayashi organized the southern area of the island in and around the mountain as a semi-independent sector, with his main defensive zone built up in the north. The expected American naval and air bombardment prompted the creation of an extensive network of tunnels connecting otherwise disparate fighting positions, so that a pillbox that had been cleared could be reoccupied later. This network of bunkers and pillboxes strongly favored the defense, and was designed for protracted resistance. For instance, the Nanpo Bunker (Southern Area Islands Naval Air HQ), which was east of Airfield Number 2, had enough food, water, and ammunition for the Japanese to hold out for three months. The bunker was 90 feet underground, and had tunnels running in various directions. Approximately five hundred 55-gallon drums filled with water, kerosene, and fuel oil for generators were stored inside the complex. Gasoline-powered generators allowed for radios and lighting to be operated underground.
By the time the Americans invaded on 19 February 1945, 18 km (11 mi) of a planned 27 km (17 mi) of tunnels had been dug. Besides the Nanpo Bunker, there were numerous other command centers and barracks that were 75 feet below ground. Tunnels allowed for troops to move undetected between various defensive positions. Hundreds of hidden artillery and mortar positions were placed all over the island, and many areas were extensively mined. Among the Japanese weapons were 320 mm spigot mortars and a variety of explosive rockets. Nonetheless, the Japanese supply situation was inadequate. Troops were supplied 60% of the ammunition normally considered sufficient for single engagement by one division, and food for no more than four months.
Numerous Japanese sniper nests and camouflaged machine gun positions were set up. Kuribayashi engineered the defenses so that every part of Iwo Jima was subject to Japanese defensive fire. He also received a handful of kamikaze pilots to use against the enemy fleet; their attacks during the battle killed 318 American sailors. However, against his wishes, Kuribayashi's superiors on Honshu ordered him to erect some beach defenses.
Starting on 15 June 1944, the U.S. Navy and the U.S. Army Air Forces began shore bombardment and air raids against Iwo Jima, which would become the longest and most intense preliminary bombardments in the Pacific Theater. They consisted of a combination of naval artillery attacks and aerial bombings, which would last for nine months. Unaware of Kuribayashi's tunnel defense system, some American planners assumed that most of the Japanese garrison had been killed by the constant bombing raids.
On 17 February 1945 the destroyer escort USS Blessman deployed Underwater Demolition Team 15 (UDT-15) onto Iwo Jima's Blue Beach for reconnaissance. They were spotted by Japanese infantry and fired upon, killing one American diver. On the evening of 18 February, Blessman was hit with a bomb by Japanese aircraft, killing 40 sailors, including 15 members of the UDT.
Major General Harry Schmidt, commander of the Marine landing force, requested a 10-day heavy bombardment of the island immediately preceding his planned amphibious assault. However, Rear Admiral William H. P. Blandy, commander of the Amphibious Support Force (Task Force 52), believed that such a bombardment would not allow him time to replenish his ships' ammunition before the landings; he thus refused Schmidt's request. Schmidt then asked for nine days of shelling; Blandy again refused and insisted upon a three-day bombardment. This decision was resented among the Marines in the landing force. After the war, Lieutenant General Holland M. "Howlin' Mad" Smith, commander Expeditionary Troops (Task Force 56, which consisted of Schmidt's Fifth Amphibious Corps), bitterly complained that a frequent lack of supporting naval gunfire had cost Marine lives throughout the Allied island-hopping campaign.
Each heavy warship was assigned an area on Iwo Jima to saturate with shells, ultimately covering the entire island. Each warship fired for approximately six hours before stopping for a certain amount of time. Poor weather on D-3 (three days before the landings) led to uncertain results for that day's bombardment. On D-2, the time and care that the Japanese had taken in preparing their artillery positions became clear. When heavy cruiser USS Pensacola got within range of Japanese shore batteries, the ship was quickly hit 6 times and suffered 17 dead. Later, 12 small craft attempting to land a UDT were all struck by Japanese fire and quickly retired. While aiding these vessels, the destroyer USS Leutze was also hit and suffered 7 dead. On D-1, Blandy's gunners were once again hampered by rain and clouds. Schmidt summed up his feelings by stating, "We only got about 13 hours worth of fire support during the 34 hours of available daylight."
The limited bombardment had a questionable impact on the enemy since the Japanese were heavily dug-in and well fortified. The craters left behind by the barrage also provided additional cover for the defenders, while hampering the attackers' advance. Despite this, many bunkers and caves were destroyed during the bombardment, giving it some limited success. The Japanese had been preparing for this battle since March 1944, which gave them a significant advantage. By the time of the landing, about 450 American ships were located off Iwo Jima, and the battle ultimately involved about 60,000 U.S. Marines and several thousand U.S. Navy Seabees.
21,060 total men under arms Lieutenant General Tadamichi Kuribayashi, commanding Colonel Tadashi Takaishi, chief of staff
During the night of 18 February 1945, Vice Admiral Marc Mitscher's large carrier force, Task Force 58, arrived off Iwo Jima. Also in this flotilla was Admiral Raymond A. Spruance, the overall commander for the invasion, in his flagship USS Indianapolis. Smith was once again deeply frustrated that Mitscher's powerful carrier group had been bombing the Japanese home islands instead of softening the defenses of Iwo Jima. Mitscher's fliers did, however, assist the additional surface vessel bombardment that accompanied the launch of the amphibious landing craft toward the island.
Unlike many days during the three-day preliminary bombardment, D-Day dawned clear and bright. At 08:59, one minute ahead of schedule, the first wave of Marines landed on the beaches of the southeastern coast of Iwo Jima. Under Major Howard Connor, 5th Marine Division signal officer, six Navajo code talkers worked around the clock during the first two days of the battle. These six men sent and received over 800 messages, all without error. Connor later stated, "Were it not for the Navajos, the Marines would never have taken Iwo Jima."
Unfortunately for the landing force, the planners at Pearl Harbor severely misjudged the situation that would face Schmidt's Marines. The beaches had been described as "excellent," and the thrust inland was expected to be "easy." The apparent lack of a vigorous Japanese response to the landings led the Navy to conclude that its bombardment had effectively suppressed the Japanese defenses. The Marines initially began deployment on the beach in good order, but the landings swiftly became congested due to the loose volcanic ash that covered the island. After allowing the Americans to concentrate men and materiel on the beach for just over an hour, throughout which they maintained cohesive fire discipline, the Japanese opened fire. Shortly after 10:00 machine guns, mortars, and heavy artillery began to rain down on the crowded beach.
Furthermore, after crossing the beach, the Marines were faced with 15 ft-high (4.6 m) slopes of soft black volcanic ash. This ash allowed for neither secure footing nor the construction of foxholes to protect the Marines from hostile fire. However, the ash did help to absorb some of the fragments from Japanese artillery.
The Japanese crews manning the heavy artillery in Mount Suribachi opened reinforced steel doors shielding their positions in order to fire, and then closed them immediately afterward to prevent counterfire from the Marines and U.S. Navy gunners. This made it exceedingly difficult for American units to destroy a Japanese artillery piece. To make matters worse for the Americans, most bunkers were connected to the elaborate tunnel system that ran through most of the island, such that bunkers that were cleared with flamethrowers and grenades were often reoccupied shortly afterwards by Japanese troops moving underground. This tactic caused many casualties among the Marines, as they walked past reoccupied bunkers without expecting to suddenly take fresh fire from them.
Time-Life correspondent Robert Sherrod described the landing simply as "a nightmare in hell."
Amtracs, unable to gain traction in the black ash, made no progress up the slopes dominating the beach; their Marine passengers had to dismount and slog forward on foot. Men of Naval Construction Battalions 31 and 133, braving enemy fire, were eventually able to bulldoze roads off of the beach. This allowed the Marines to finally make some progress inland and get off the beach, which had become overcrowded with both men and materiel as follow-on waves of landing craft continued to unload. Casualties on the beach were heavy, with historian Derrick Wright noting "in virtually every shell hole there lay at least one dead Marine."
By 11:30, some Marines had managed to reach the southern tip of Airfield No. 1, the seizure of which had been one of the original American objectives for the first day. The Marines endured a fanatical charge by the over 100 Japanese troops, but were able to keep their toehold on Airfield No. 1 as night fell.
In the left-most sector of the landings, the Americans did manage to achieve one of their objectives for the battle that day. Led by Colonel Harry B. "Harry the Horse" Liversedge, the 28th Marines drove across the island at its narrowest width, around 800 m (870 yd), thereby isolating the Japanese dug in on Mount Suribachi.
The rightmost landing area was dominated by Japanese fortifications located at "the Quarry". The 25th Marine Regiment conducted a two-pronged attack to neutralize this position. 2nd Lieutenant Benjamin Roselle, part of a ground team directing naval gunfire, described the following experience:
The 25th Marines' 3rd Battalion had landed approximately 900 men on the island that morning. Japanese resistance at the Quarry was so fierce that by nightfall, only 150 Marines were left in fighting condition, an 83.3% casualty rate.
By the evening of 19 February, 30,000 Marines had landed. About 40,000 more would follow. Aboard the command ship USS Eldorado, Smith saw the lengthy casualty reports and was briefed on the slow progress of the ground forces. To the war correspondents covering the operation, Smith remarked: "I don't know who he is, but the Japanese general running this show is one smart bastard."
In the days after the landings, the Marines expected the usual Japanese banzai charge during the night. This had been the standard Japanese defense strategy in previous island battles against enemy ground forces in the Pacific, such as during the Battle of Saipan in June 1944. In those attacks, for which the Marines had usually been at least somewhat prepared, the majority of Japanese attackers had been killed and the overall Japanese fighting strength significantly degraded. However, General Kuribayashi had strictly forbidden these "human wave" attacks by the Japanese infantrymen, considering them a futile waste of resources.
The fighting near the beachhead remained intense, and the American advance was stalled by numerous defensive positions augmented by artillery. Marines were frequently ambushed by Japanese troops who sprang out of previously-unseen tunnels. At night, the Japanese left their defenses in small groups to attack American foxholes under cover of darkness, and U.S. Navy ships began firing star shells to illuminate the battlefield. Similar to previous battles on Japanese-held islands, on Iwo Jima Japanese soldiers who knew English were used to harass and deceive Marine units; English-speaking IJA troops often yelled "corpsman", pretending to be a wounded Marine, in order to lure and kill the U.S. Navy medical personnel attached to Marine infantry companies.
The Marines learned that firearms were relatively ineffective against the Japanese defenders, and turned to flamethrowers and grenades to flush the Japanese troops out of their tunnels. One of the technological innovations of the battle, the eight Sherman M4A3R3 medium tanks equipped with a flamethrower ("Ronson" or "Zippo" tanks), proved highly effective at clearing hardened Japanese positions. The Shermans were difficult to disable, often requiring Japanese defenders to assault them in the open, where they were vulnerable to the superior numbers and firepower of the Marines.
Close air support was initially provided by fighters from escort carriers off the coast. This shifted over to the 15th Fighter Group, flying P-51 Mustangs, after they arrived on the island on 6 March. Similarly, illumination rounds (flares), used to light up the battlefield at night, were initially provided by ships but were later provided by land-based artillery. Navajo code talkers were part of the American ground communications system, along with walkie-talkies and SCR-610 backpack radio sets.
After running out of water, food and most other supplies, Japanese troops became desperate toward the end of the battle. Kuribayashi, who had argued against banzai attacks for most of the fighting, realized that defeat was imminent.
Marines began to face increasing numbers of nighttime attacks; these were only repelled by a combination of machine-gun fire and artillery support. At times, the Marines engaged in hand-to-hand fighting to repel the Japanese attacks. Once the landing area was secured, more troops and heavy equipment came ashore, and the Americans proceeded north to capture the airfields and the remainder of the island. Most Japanese soldiers fought to the death.
Raising the Flag on Iwo Jima is a black and white photograph taken by Joe Rosenthal depicting six Marines from E Company, 2nd Battalion, 28th Marines, raising a U.S. flag atop Mount Suribachi on 23 February 1945, which was the second of two flag-raisings on the site that day. The photograph was extremely popular, being reprinted in thousands of publications. Later, it became the only photograph to win the Pulitzer Prize for Photography in the same year as its publication, and ultimately came to be regarded as one of the most significant and recognizable images of the war, and possibly the most reproduced photograph of all time. The flag raising picture was later used by Felix de Weldon to sculpt the Marine Corps War Memorial which is located adjacent to Arlington National Cemetery since 1954.
Three of the six Marines depicted in the photograph, Sergeant Michael Strank, Corporal Harlon Block, and Private First Class Franklin Sousley, were killed in action days after the flag-raising. Surviving flag-raiser Private First Class Ira Hayes, together with Private First Class Rene Gagnon and Navy hospital corpsman Pharmacist's Mate Second Class John Bradley, became celebrities upon their participation in a war bond selling tour after the battle. Three subsequent Marine Corps investigations into the identities of the six men in the photograph determined: in 1946 and 1947, that Harlon Block was incorrectly identified as Henry Hansen (both were killed six days after the photo was taken); in May and June 2016, that John Bradley was not in the photograph and Private First Class Harold Schultz was; and in 2019, that Rene Gagnon was not in the photograph and Private First Class Harold Keller was.
By the morning of 23 February, Mount Suribachi was effectively cut off above ground from the rest of the island. The Marines knew there was an extensive network of below-ground defenses, and that in spite of its isolation above ground, the volcano was still connected via the tunnel network. They expected a fierce fight for the summit. Two small patrols from two rifle companies from the 2/28 Marines were sent up the volcano to reconnoiter routes on the mountain's north face. The recon patrols made it to the summit and scrambled down again, reporting any contact to the 2/28 Marines commander, Lieutenant Colonel Chandler W. Johnson.
Popular accounts embroidered by the press in the aftermath of the release of the photo of the flag raising, had the Marines fighting all the way up to the summit. Although the Marine riflemen expected an ambush, the larger patrol going up afterwards encountered a few defenders once on top and after the flag was raised. The majority of the Japanese troops stayed in the tunnel network during shelling, only occasionally attacking in small groups, and were generally all killed.
Johnson called for a reinforced platoon size patrol from E Company to climb Suribachi and seize and occupy the crest. The patrol commander, First Lieutenant Harold G. Schrier, was handed the battalion's American flag to be raised on top to signal Suribachi's capture, if they reached the summit. Johnson and the Marines anticipated heavy fighting, but the patrol encountered only a small amount of sniper fire on the way up the mountain. Once the top was secured by Schrier and his men, a length of Japanese water pipe was found there among the wreckage, and the American flag was attached to the pipe and then raised and planted on top of Mount Suribachi which became the first foreign flag to fly on Japanese soil. Photographs of the flag and some of the patrol members around it were taken by Marine photographer Louis R. Lowery, the only photographer who had accompanied Schrier's patrol up the mountain.
As the flag went up, Secretary of the Navy James Forrestal had just landed on the beach at the foot of Mount Suribachi and decided that he wanted the flag as a souvenir. Johnson believed that the flag belonged to the 2nd Battalion, 28th Marines, who had captured that section of the island. In the early afternoon, Johnson sent Gagnon, a runner (messenger) from his battalion for E Company, to take a larger flag up the volcano to replace the smaller and less visible flag. The replacement flag was attached to a heavier section of water pipe, and six Marines proceeded to raise it into place as the smaller flag was taken down and delivered to the battalion's headquarters down below. It was during this second flag-raising that Rosenthal took the photograph "Raising the Flag on Iwo Jima". The second flag flew on Mount Suribachi until it was taken down on 14 March, when at the same time an American flag was officially raised during a ceremony at the V Amphibious Corps command post near Mount Suribachi. The official flag raising was ordered by Holland Smith and attended by Erskine and some members of the 3rd Marine Division.
Despite the loss of Mount Suribachi on the south end of the island, the Japanese still held strong positions on the north end. The rocky terrain vastly favored defense, even more so than Mount Suribachi, which was much more vulnerable to naval artillery fire. The fortifications on the northern section of Iwo Jima were also more impressive than those at the southern end of the island. Remaining under the command of Kuribayashi was the equivalent of eight infantry battalions, a tank regiment, and two artillery and three heavy mortar battalions. There were also about 5,000 gunners and naval infantry available for combat. The most arduous task left to the Marines was seizing the Motoyama Plateau, with its distinctive Hill 382 and "Turkey knob", as well as the area in between, referred to as "the Amphitheater". These obstacles formed the basis of what came to be known to the Marines as the "meatgrinder". While these Japanese positions were being reduced on the right flank, American units on the left were clearing out Hill 362 with just as much difficulty.
The Marines' overall objective at this point was to take control of Airfield No. 2 in the center of the island. However, every "penetration seemed to become a disaster" as "units were raked from the flanks, chewed up, and sometimes wiped out. Tanks were destroyed by interlocking fire or were hoisted into the air on the spouting fireballs of buried mines". As a result, the fighting bogged down, and American casualties piled up rapidly. Even capturing these points did not guarantee that the captured territory was secure, since a previously cleared fortification could be reoccupied by Japanese troops utilizing the island's tunnel system. As such, it was said that "[the Marines] could take these heights at will, and then regret it".
American troops observed that during bombardments, the Japanese would hide their guns and themselves in caves, only to reemerge when Marine units began to advance and lay down devastating fire on them. Over time, the Japanese learned basic American combat tactics, which usually involved laying down a heavy bombardment before an infantry attack. Consequently, Erskine ordered the 9th Marine Regiment to attack under the cover of darkness with no preliminary barrage. This was a resounding success, with many Japanese soldiers killed while still asleep. This became a key moment in the capture of Hill 362. The hill held such strategic importance that the Japanese organized a counterattack to retake it the following night. Although Kuribayashi had forbidden the massed infantry charges often used by the Japanese in previous battles in the Pacific, the local IJA commander of the area decided on a banzai charge with the optimistic goal of recapturing Mount Suribachi.
On the evening of 8 March, Captain Samaji Inouye and his 1,000 men charged the American lines, inflicting 347 casualties (90 deaths). The Marines counted 784 dead Japanese soldiers the next day. The same day, elements of the 3rd Marine Division reached the northern coast of the island, splitting Kuribayashi's defenses in two. There was also a kamikaze air attack (the only one of the battle) on the ships anchored at sea on 21 February, which resulted in the sinking of the escort carrier USS Bismarck Sea, severe damage to USS Saratoga, and slight damage to the escort carrier USS Lunga Point, an LST, and a transport.
Although the island was declared secure at 18:00 on 16 March (25 days after the landings), the 5th Marine Division still faced Kuribayashi's main stronghold, located in a gorge 640 m (700 yd) long at the northwestern end of the island. On 21 March, the Marines destroyed the command post in the gorge with four tons of explosives, and on 24 March Marines sealed the remaining caves at the northern tip of the island. However, on the night of 25 March, a 300-man Japanese force launched a final counterattack in the vicinity of Airfield No. 2. Army pilots, Seabees, and Marines of the 5th Pioneer Battalion and 28th Marines fought the Japanese force for up to 90 minutes, suffering heavy casualties (53 killed, 120 wounded). Although still a matter of speculation due to conflicting accounts from surviving Japanese veterans, it is possible that Kuribayashi personally led this final assault, which - unlike the loud banzai charge of previous battles - was conducted in silence by the Japanese infantrymen. If he did participate in this assault, Kuribayashi would have been the highest ranking Japanese officer to have personally led an attack during World War II. Additionally, this would also be a departure from the normal practice of commanding Japanese officers committing seppuku behind the lines while their subordinates perished in a last-ditch banzai charge, as occurred during the battles of Saipan and Okinawa. The island was officially declared secure at 09:00 on 26 March.
Once the island was officially declared secure, the U.S. Army's 147th Infantry Regiment was ostensibly there to act as a garrison force, but soon found itself locked in a bitter struggle against thousands of Japanese holdouts engaging in a guerrilla campaign to harass the Americans. Utilizing caves and tunnel systems, the remnants of the Japanese garrison conducted numerous attacks on American forces. For three months, the 147th slogged across the island, using flamethrowers, grenades, and satchel charges to dig out the enemy, ultimately killing some 1,602 Japanese soldiers in small unit actions (along with many others who died in sealed caves) while suffering fifteen men killed in action and another 144 wounded. The Ohioans were also credited with capturing 867 Japanese soldiers; combined with the number of enemy soldiers killed by the regiment, this casualty figure represented over 10% of the original Japanese garrison.
The United States M2 flamethrower was heavily used in the Pacific. It features two tanks containing fuel and compressed gas respectively, which are combined and ignited to produce a stream of flaming liquid out of the tip.
These flamethrowers were used to kill Japanese holed into pillboxes, buildings and caves. A battalion would assign one flamethrower per platoon with one reserve flamethrower in each group. Flamethrower operators were usually in more danger than regular troops as the short range of their weapon required close combat, and the visibility of the flames on the battlefield made them a prominent target for snipers. Still, they were essential to breaking the dug-in enemy.
For better protection, flamethrowers were mounted on flame tanks, and one battalion commander called these the "best single weapon of the operation." Prior to Saipan the Marine Corps had left flamethrowing tank development to the Army. They had placed an order with the Army for nine tanks per division. At Schofield Barracks in Hawaii, Colonel Unmacht's top secret "Flame Thrower Group" located eight M4A3 Sherman medium tanks to convert for Operation Detachment. His Seabees, from the 117th CB, worked to combine the best features of three different flame units, the Ronson, the Navy model I and the Navy Mk-1, which soon led to the far better CB-H2. The U.S. Army Chemical Corps variously identified these tanks as POA-CWS-H1, (Pacific Ocean Area-Chemical Warfare Section-Hawaii) CWS-POA-H2, CWS-POA-H1 H2, OR CWS-"75"-H1 H2 mechanized flamethrowers. U.S. Marine and U.S. Army observer documents from Iwo Jima refer to them as the CB-Mk-1 or CB-H1. Marines on the lines simply called them the Mark I. The official USMC designation was "M4 A3R5". The Japanese referred to them as M1 tanks, and it is speculated that they did so because of a poor translation of "MH-1".
On Iwo Jima the flame tanks all landed on D-day and went into action on D+2, sparingly at first. As the battle progressed, portable flame units wielded on foot sustained casualty rates up to 92%, leaving few troops trained to use the weapon. More and more calls came for the Mark-1 flame tanks, to the point that the Marines became dependent upon them and would hold up their assault until a flame tank was available. Since each tank battalion had only four, they were pooled among units and would dispatch from their respective refueling locations as the battle progressed. Towards the end of the battle, 5th Marine tanks expended between 5,000 to 10,000 US gal (19,000 to 38,000 L) of napalm per day.
Japanese holdouts on the island, including two of Lieutenant Toshihiko Ohno's men, Yamakage Kufuku [sic] (山蔭光福, Yamakage Kōfuku) and Matsudo Linsoki [sic] (松戸利喜夫, Matsudo Rikio), lasted four years without being caught, and finally surrendered on 6 January 1949.
Though ultimately victorious, the American victory at Iwo Jima had been extremely costly. According to the Navy Department Library, "the 36-day assault resulted in more than 26,000 American casualties, including 6,800 dead." By comparison, the much larger scale 82-day Battle of Okinawa lasting from early April until mid-June 1945 (involving five U.S. Army and two Marine Corps divisions) resulted in over 62,000 U.S. casualties, of whom over 12,000 were killed or missing. Iwo Jima was also the only U.S. Marine battle where the American casualties exceeded those of the Japanese, although Japanese combat deaths numbered three times as many as American KIA. Two U.S. Marines were captured during the battle, neither of whom survived their captivity.
The USS Bismarck Sea was sunk during the battle, the last U.S. aircraft carrier sunk in World War II. Twenty Grumman FM-2 Wildcat fighters and 11 Grumman TBM Avenger torpedo bombers went down with Bismarck Sea. The USS Saratoga was so severely damaged that she took no part in either combat or transportation duties for the rest of the war, and became a training ship. Thirty-one Grumman F6F Hellcat fighters and 9 Grumman TBM Avenger torpedo bombers were destroyed by the kamikaze attack on Saratoga. Because all civilians had been evacuated, there were no civilian casualties on Iwo Jima, unlike at Saipan and Okinawa.
In hindsight, given the number of casualties, the necessity and long-term significance of the island's capture to the outcome of the war became a contentious issue and remains disputed. The Marines, who conducted the landings themselves and took the vast majority of the casualties, had not been consulted in the planning of the operation. As early as April 1945, retired Chief of Naval Operations William V. Pratt stated in Newsweek magazine that the "expenditure of manpower to acquire a small, God-forsaken island, useless to the Army as a staging base and useless to the Navy as a fleet base ... [one] wonders if the same sort of airbase could not have been reached by acquiring other strategic localities at lower cost."
The lessons learned on Iwo Jima served as guidelines for the Battle of Okinawa in April 1945, and influenced American planning for an invasion of the Japanese Home Islands. For example, on Okinawa, "because of the casualties taken at Iwo Jima on the first day, it was decided to make the preparatory bombardment the heaviest yet delivered on to a Pacific island". Additionally, in the planning for a potential invasion of Japan itself, it was taken into account that around a third of the troops committed to Iwo Jima, and later again at Okinawa, had been killed or wounded.
The justification behind Iwo Jima's strategic importance to the United States' war effort revolves around the island's role as a landing and refueling site for long-range fighter escorts. These escorts ultimately proved both impractical and unnecessary, and only ten such missions were flown from Iwo Jima. By the time Iwo Jima had been captured, the bombing campaign against Japan had switched from daylight precision bombing to nighttime incendiary attacks, so fighter escorts were of limited utility.
Japanese fighter aircraft based on Iwo Jima occasionally attacked U.S. Army Air Force bombers, which were vulnerable en route to Japan because they were heavily laden with bombs and fuel. However, the impact of Iwo Jima-based Japanese interceptors on the American bombing effort was marginal; in the three months before the invasion, only 11 B-29s had been lost to Japanese aircraft flying out of the Bonin Islands. The Superfortresses largely found it unnecessary to make any major detour around the island. Capturing the island neutralized Japanese air attacks on the Marianas, but these attacks were too small to ever seriously threaten American military assets based on Saipan and Tinian.
The Japanese garrison on Iwo Jima possessed radar and was thus able to notify air defenses on the Home Islands of incoming B-29 Superfortresses flying from the Marianas. However, the capture of Iwo Jima did not affect the Japanese early-warning radar system, which continued to receive information on incoming B-29s from the island of Rota (which was never invaded).
As early as 4 March 1945, while fighting was still taking place, the B-29 Dinah Might of the USAAF 9th Bomb Group reported it was low on fuel near the island and requested an emergency landing. Despite enemy fire, the airplane landed on the Allied-controlled section of the island (South Field) without incident and was serviced, refueled and departed.
In all, 2,251 B-29 landings on Iwo Jima were recorded during the war. Author J. Robert Moskin records that 1,191 fighter escorts and 3,081 strike sorties were flown from Iwo Jima against Japan. A more recent Air Force study found the contribution of VII Fighter Command, based on Iwo Jima, to be superfluous. Another rationale for capturing the island was to provide a base for shorter-range B-24 Liberator bombers against Japan, but no significant B-24 bombing campaign ever materialized.
Some downed B-29 crewmen were saved by air-sea rescue aircraft and vessels operating from the island, but Iwo Jima was just one of many islands that could have been used for such a purpose. As for the importance of the island as a landing and refueling site for bombers, Marine Captain Robert Burrell, then a history instructor at the United States Naval Academy, suggested that only a small proportion of the 2,251 landings were for genuine emergencies, with the vast majority possibly being for minor technical checkups, training, or refueling. According to Burrell,
The "emergency landing" thesis counts every B-29 landing on Iwo Jima as an emergency and asserts that capturing the island saved the lives of the nearly 25,000 crewmen of all 2,251 planes (2,148 B-29 crewmen were killed in combat during the entire war in all theaters). However, of the nearly 2,000 B-29s which landed from May–July 1945, more than 80% were for routine refueling. Several hundred landings were made for training purposes, and most of the remainder were for relatively minor engine maintenance. During June 1945, which saw the largest number of landings, none of the more than 800 B-29s that landed on the island did so because of combat damage. Of the aircraft that would have been lost without being able to land, air-sea rescue figures indicate that 50% of crewmen who ditched at sea survived, so even if Iwo Jima had not been taken the estimate of the supposedly potential 25,000 dead crewmen from airplanes crashing into the ocean should be dwindled down to 12,500.
According to Robert S. Burrell, author of The Ghosts of Iwo Jima, the very losses formed the basis for a "reverence for the Marine Corps" that not only embodied the "American national spirit" but ensured the "institutional survival" of the Marine Corps.
The following table lists for each ship badly damaged in the Battle of Iwo Jima, the dates they received hits, the cause, the type of ship, and the casualties inflicted during 17–28 February. The carrier USS Lunga Point, which received light damage, was listed because of the importance of escort carriers in the battle.
The Medal of Honor is the highest military decoration awarded by the United States government. It is bestowed on a member of the United States Armed Forces who distinguishes himself by "... conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty while engaged in an action against an enemy of the United States ..." Because of its nature, the medal is commonly awarded posthumously.
The Medal of Honor was awarded to 22 Marines (12 posthumously), and 5 were presented to sailors, 4 of whom were hospital corpsmen (2 posthumously) attached to Marine infantry units. The medals awarded for the battle accounted for 28% of the 82 awarded to Marines in World War II.
At the time of his death on 29 June 2022, Marine Hershel W. Williams was the last living Medal of Honor recipient from World War II. He received his medal for actions in the Battle of Iwo Jima.
The Marine Corps Iwo Jima Memorial was dedicated on 10 November 1954 at Arlington National Cemetery.
The United States Navy has commissioned two ships with the name USS Iwo Jima (LPH-2) (1961–1993) and USS Iwo Jima (LHD-7) (2001–present).
The first large-scale reunion on the island was held in 1970 on the 25th anniversary of the battle. The event was sponsored by the Fifth Marine Division Association and included both American and Japanese veterans of the battle. Other notable attendees included then Brigadier General William K. Jones commander of the 3rd Marine Division and NBC’s senior correspondent in Asia John Rich. The widows of General Tadamichi Kuribayashi and Colonel Takeichi Nishi also attended events with American veterans held in Tokyo.
On 19 February 1985, the 40th anniversary of the landings on Iwo Jima, an event called the "Reunion of Honor" was held (the event has been held annually since 2002). Veterans of both sides who fought in the battle attended the event. The place was the invasion beach where U.S. forces landed. A memorial on which inscriptions were engraved by both sides was built at the center of the meeting place. Japanese attended at the mountain side, where the Japanese inscription was carved, and Americans attended at the shore side, where the English inscription was carved. After unveiling and offering of flowers were made, the representatives of both countries approached the memorial; upon meeting, they shook hands. The combined Japan-U.S. memorial service of the 50th anniversary of the battle was held in front of the monument in February 1995. Further memorial services have been held on later anniversaries.
The importance of the battle to Marines today is demonstrated in pilgrimages made to the island, and specifically the summit of Suribachi. Marines will often leave dog tags, rank insignia, or other tokens at the monuments in homage. Iwo Jima Day is observed annually on 19 February in the Commonwealth of Massachusetts with a ceremony at the State House.
The Japanese government continues to search for and retrieve the remains of Japanese military personnel who were killed during the battle.