Battle of Iwo Jima

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Battle of Iwo Jima
Part of World War II, Pacific War
U.S. flag over the Mount Suribachi
Date February 19, 1945 - March 16, 1945 Location Iwo Jima, Japan Result U.S. victory
Combatants
United States	Empire of Japan
Commanders
Holland Smith	Tadamichi Kuribayashi
Strength
110,000	22,000
Casualties
6,825 killed in action, 1,401 died of wounds, 19,189 wounded, 494 missing Total: 27,909	20,703 dead, 216 captured Total: 20,916

The Battle of Iwo Jima was fought by the United States of America and Japan in February and March 1945, during the Pacific Campaign of World War II. The U.S. invasion, known as Operation Detachment, was aimed at capturing the airfields on Iwo Jima.

The battle was marked by some of the fiercest fighting of the campaign. The Imperial Japanese Army positions on the island were heavily fortified, with vast bunkers, hidden artillery, and 11 miles of tunnels. The battle was the first American attack on the Japanese Home Islands, and the Imperial soldiers defended their positions tenaciously; of the 22,000 Japanese soldiers present at the beginning of the battle, 20,000 were killed, and only 216 taken prisoner.

Joe Rosenthal photographed five Marines and a U.S. Navy corpsman raising the U.S. flag atop the 166 meter (546 ft) Mount Suribachi. When Rosenthal saw the rising of the flag, he quickly snapped the photograph without looking through the lens. The picture became the iconic image of the battle, and possibly the most reproduced photograph of all time.

The Island 1,800 km (1118 miles) south of Tokyo, 1,130 km (702 miles) north of Guam, and nearly halfway between Tokyo and Saipan (24.756°N, 141.290°E) It is approximately 21 square kilometers, with Mount Suribachi as its most prominent feature, at its southern tip.

Background

After the American seizure of the Marshall Islands and devastating air attacks against Truk in the Caroline Islands in February 1944, the Japanese military leadership reappraised the military situation. All indications pointed to an American drive towards the Marianas and Carolines. To counter such a move, they established an inner line of defense extending generally northward from the Carolines to the Marianas, and thence to the Ogasawara Islands. In March 1944, the Thirty-First Army, commanded by General Hideyoshi Obata, was activated for the purpose of garrisoning this inner line. The commander of the Chichi Jima garrison was placed nominally in command of Army and Navy units in the Ogasawara Islands.

Following the American seizure of bases in the Marshalls in the battles of Kwajalein and Eniwetok in February 1944, both Army and Navy reinforcements were sent to Iwo Jima. Five hundred men from the naval base at Yokosuka and an additional 500 from Chichi Jima reached Iwo Jima during March and April 1944. At the same time, with the arrival of reinforcements from Chichi Jima and the home islands, the Army garrison on Iwo Jima had reached a strength of over 5,000 men, equipped with 13 artillery pieces, 200 light and heavy machine guns, and 4,552 rifles. In addition there were a number of 120 mm coastal artillery guns, twelve heavy anti-aircraft guns, and thirty 25 mm dual-mount anti-aircraft guns.

The loss of the Marianas during the summer of 1944 greatly increased the importance of the Ogasawaras for the Japanese, who were well aware that the loss of these islands would facilitate American air raids against the home islands, disrupting war manufacturing and severely damaging civilian morale.

Final Japanese plans for the defense of the Ogasawaras were overshadowed by the fact that the Imperial Japanese Navy had already lost most of its strength and could no longer prevent American landings. Moreover, aircraft losses throughout 1944 had been so heavy that, even if war production were not affected by American air attacks, combined Japanese air strength was not expected to increase to 3,000 aircraft until March or April of 1945. Even then, these planes could not be used from bases in the home islands against Iwo Jima because their range did not exceed 900 km (559 miles); besides, all available aircraft had to be hoarded for possible use on Taiwan and adjacent islands near land bases.

In a postwar study, Japanese staff officers described the strategy applied in the defense of Iwo Jima in the following terms:

Daily bomber raids from the Marianas hit the mainland as part of Operation Scavenger. Iwo Jima served as an early warning station which radioed reports of incoming bombers back to mainland Japan, allowing Japanese air defenses to be prepared for the arrival of American bombers.

At the end of the Battle of Leyte in the Philippines, the Allies were left with a two month lull in their operations prior to the planned invasion of Okinawa. Iwo Jima was strategically important: it provided an airbase for Japanese aircraft to intercept long-range B-29 bombers and provided a haven for Japanese naval units in dire need of any support available. The capture of Iwo Jima would eliminate these problems and provide a staging area for the eventual invasion of the Japanese mainland. The distance of B-29 raids would be nearly halved, and a base would be available for P-51 Mustang fighters to escort and protect the devastating bomber raids. Intelligence sources were confident that Iwo Jima would fall in five days, unaware that the Japanese were preparing a quintessentially defensive posture, radically departing from any of their previous tactics. So successful was the Japanese preparation that it was discovered after the battle that the hundreds of tons of allied bombs and thousands of rounds of heavy naval gunfire left the Japanese defenders almost unscathed, and ready to wreak losses on the U.S. Marines unparalleled up to that point in the Pacific War. In the light of the optimistic intelligence reports, the decision was made to invade Iwo Jima: the landing was designated Operation Detachment.

Japanese planning

When he arrived, some 80 fighter aircraft were stationed on Iwo Jima, but by early July only four remained. A United States Navy force then came within sight of the island and bombarded it for two days, destroying every building and the four remaining aircraft.

Much to the surprise of the Japanese garrison on Iwo Jima, there was no American attempt to invade the island during the summer of 1944. There was little doubt that in time the Americans would attack, and General Kuribayashi was more determined than ever to exact the heaviest possible price for Iwo Jima, although the lack of naval and air support meant that Iwo Jima could not hold out indefinitely against an invader with sea and air supremacy.

View of the invasion beach from the top of Mount Suribachi

By late July Kuribayashi had evacuated all civilians from the island. Lieutenant General Hideyoshi Obata, commanding general of the 31st Army, early in 1944 had been responsible for the defense of Iwo Jima prior to his return to the Marianas. Following the doctrine that an invasion had to be met practically at the water's edge, Obata had ordered the emplacement of artillery and the construction of pillboxes near the beaches. General Kuribayashi had a different strategy. Instead of attempting to hold the beaches, he planned to defend them with a sprinkling of automatic weapons and infantry. Artillery, mortars, and rockets would be emplaced on the foot and slopes of Mount Suribachi, as well as in the high ground to the north of Chidori airfield.

The reason for Kuribayashi's departure from the water's edge defense strategy which had been the normal practice for the Japanese Imperial Army, was that he predicted that American air and naval bombardments would destroy any defenses on the beaches. It had been used at Saipan to great losses for the Japanese. For water's edge defense to work, it needed support from the air and sea, none of which the Japanese Imperial Navy was capable of mounting at this point anymore. However other military branches, especially the navy were still insistent on the water's edge defense and demanded that Kuribayashi see to it. In the end Kurabayashi had some pillboxes built at the beach as a token measure. The pillboxes were destroyed by American bombardment.

Caves and tunnels

A prolonged defense of the island required the preparation of an extensive system of caves and tunnels, for the naval bombardment had clearly shown that surface installations could not withstand extensive shelling. To this end, mining engineers were dispatched from Japan to draw blueprints for projected underground fortifications that would consist of elaborate tunnels at varying levels to assure good ventilation and minimize the effect of bombs or shells exploding near the entrances or exits.

At the same time, reinforcements were gradually beginning to reach the island. As commander of the 109th Infantry Division, General Kuribayashi decided first of all to shift the 2nd Independent Mixed Brigade, consisting of about 5,000 men under Major General Kotau Osuga, from Chichi to Iwo Jima. With the fall of Saipan, 2,700 men of the 145th Infantry Regiment, commanded by Colonel Masuo Ikeda, were diverted to Iwo Jima. These reinforcements, who reached the island during July and August 1944, brought the strength of the garrison up to approximately 12,700 men. Next came 1,233 members of the 204th Naval Construction Battalion, who quickly set to work constructing concrete pillboxes and other fortifications.

On 10 August 1944, Rear Admiral Rinosuke Ichimaru reached Iwo Jima, shortly followed by 2,216 naval personnel, including naval aviators and ground crews. The admiral, a renowned Japanese aviator, had been crippled in an airplane crash in the mid-twenties and, ever since the outbreak of the war, had chafed under repeated rear echelon assignments.

Artillery

Japanese 120 mm gun after the battle

Next to arrive on Iwo Jima were artillery units and five anti-tank battalions. Even though numerous supply ships en route to Iwo Jima were sunk by American submarines and aircraft, substantial quantities of materiel did reach Iwo Jima during the summer and autumn of 1944. By the end of the year, General Kuribayashi had available to him 361 artillery pieces of 75 mm or larger caliber, a dozen 320 mm mortars, 65 medium (150 mm) and light (81 mm) mortars, 33 naval guns 80 mm or larger, and 94 anti-aircraft guns 75 mm or larger. In addition to this formidable array of large caliber guns, the Iwo Jima defenses could boast more than 200 20 mm and 25 mm anti-aircraft guns and 69 37 mm and 47 mm antitank guns. The firepower of the artillery was further augmented with a variety of rockets varying from an eight-inch type that weighed 90 kg and could travel 2–3 km, to a giant 250 kg projectile that had a range of more than 7 km. Altogether, 70 rocket guns and their crews reached Iwo Jima.

In order to further strengthen the Iwo defenses, the 26th Tank Regiment, which had been stationed at Pusan, Korea after extended service in Manchuria, received orders for Iwo Jima. The officer commanding this regiment was Lieutenant Colonel Baron Takeichi Nishi. The regiment, consisting of 600 men and 28 tanks, sailed from Japan in mid-July on board the Nisshu Maru. As the ship, sailing in a convoy, approached Chichi Jima on 18 July 1944, it was torpedoed by an American submarine, USS Cobia. Even though only two members of the 26th Tank Regiment were killed, all of the regiment's 28 tanks went to the bottom of the sea. It would be December before these tanks could be replaced, 22 of which finally reached Iwo Jima.

Initially, Colonel Nishi had planned to employ his armor as a type of "roving fire brigade", to be committed at focal points of combat. The rugged terrain precluded such employment and in the end, under the colonel's watchful eyes, the tanks were deployed in static positions. They were either buried or their turrets were dismounted and so skillfully emplaced in the rocky ground that they were practically invisible from the air or the ground.

For the remainder of 1944, the construction of fortifications on Iwo also went into high gear. The Japanese were quick to discover that the black volcanic ash that existed in abundance all over the island could be converted into concrete of superior quality when mixed with cement. Pillboxes near the beaches north of Mount Suribachi were constructed of reinforced concrete, many of them with walls four feet thick. At the same time, an elaborate system of caves, concrete blockhouses, and pillboxes were established. One of the results of American air attacks and naval bombardment in the early summer of 1944 had been to drive the Japanese so deep underground that eventually their defenses became virtually immune to air or naval bombardment.

While the Japanese on Peleliu Island in the Western Carolines, also awaiting American invasion, had turned the improvement of natural caves into an art, the defenders of Iwo developed it into a science. Because of the importance of the underground positions, 25% of the garrison was detailed to tunneling. Positions constructed underground ranged in size from small caves for a few men to several underground chambers capable of holding 300 or 400 men. In order to prevent personnel from becoming trapped in any one excavation, the subterranean installations were provided with multiple entrances and exits, as well as stairways and interconnecting passageways. Special attention had to be paid to providing adequate ventilation, since sulphur fumes were present in many of the underground installations. Fortunately for the Japanese, most of the volcanic stone on Iwo was so soft that it could be cut with hand tools.

General Kuribayashi established his command post in the northern part of the island, about 500 m northeast of Kita village and south of Kitano Point. This installation, 20 m underground, consisted of caves of varying sizes, connected by 150 m of tunnels. Here the island commander had his own war room in one of three small concrete enclosed chambers; the two similar rooms were used by the staff. Farther south on Hill 382, the second highest elevation on the island, the Japanese constructed a radio and weather station. Nearby, on an elevation just southeast of the station, an enormously large blockhouse was constructed which served as the headquarters of Colonel Chosaku Kaidō, who commanded all artillery on Iwo Jima. Other hills in the northern portion of the island were tunnelled out. All of these major excavations featured multiple entrances and exits and were virtually invulnerable to damage from artillery or aerial bombardment. Typical of the thoroughness employed in the construction of subterranean defenses was the main communications center south of Kita village, which was so spacious that it contained a chamber 50 m long and 20 m wide. This giant structure was similar in construction and thickness of walls and ceilings to General Kuribayashi's command post. A 150 m tunnel 20 m below the ground led into this vast subterranean chamber.

Perhaps the most ambitious construction project to get under way was the creation of an underground passageway designed to link all major defense installations on the island. As projected, this passageway was to have attained a total length of almost 27 km (17 miles). Had it been completed, it would have linked the formidable underground installations in the northern portion of Iwo Jima with the southern part of the island, where the northern slope of Mount Suribachi alone harbored several thousand yards of tunnels. By the time the Marines landed on Iwo Jima, more than 18 km (11 miles) of tunnels had been completed.

A supreme effort was required of the Japanese personnel engaged in the underground construction work. Aside from the heavy physical labor, the men were exposed to heat from 30–50 °C (90–130 °F), as well as sulphur fumes that forced them to wear gas masks. In numerous instances a work detail had to be relieved after only five minutes. Renewed American air attacks struck the island on 8 December 1944 and became a daily occurrence until the actual invasion of the island. Subsequently, a large number of men had to be diverted to repairing the damaged airfields.

Defense planning

While Iwo Jima was being converted into a major fortress with all possible speed, General Kuribayashi formulated his final plans for the defense of the island. This plan, which constituted a radical departure from the defensive tactics used by the Japanese earlier in the war, provided for the following major points:

1. In order to prevent disclosing their positions to the Americans, Japanese artillery was to remain silent during the expected prelanding bombardment. No fire would be directed against the American naval vessels.
2. Upon landing on Iwo Jima, the Americans were not to encounter any opposition on the beaches.
3. Once the Americans had advanced about 500 m inland, they were to be taken under the concentrated fire of automatic weapons stationed in the vicinity of Motoyama airfield to the north, as well as automatic weapons and artillery emplaced both on the high ground to the north of the landing beaches and Mount Suribachi to the south.
4. After inflicting maximum possible casualties and damage on the landing force, the artillery was to displace northward from the high ground near the Chidori airfield.

In this connection, Kuribayashi stressed once again that he planned to conduct an elastic defense designed to wear down the invasion force. Such prolonged resistance naturally required the defending force to stockpile rations and ammunition. To this end the island commander accumulated a food reserve to last for two and a half months, ever mindful of the fact that the trickle of supplies that was reaching Iwo Jima during the latter part of 1944 would cease altogether once the island was surrounded by a hostile naval force.

During the final months of preparing Iwo Jima for the defense, General Kuribayashi saw to it that the strenuous work of building fortifications did not interfere with the training of units. As an initial step towards obtaining more time for training, he ordered work on the northernmost airfield on the island halted. In an operations order issued in early December, the island commander set 11 February 1945 as the target date for completion of defensive preparations and specified that personnel were to spend 70% of their time in training and 30% in construction work.

Despite intermittent harassment by American submarines and aircraft, additional personnel continued to arrive on Iwo until February 1945. By that time General Kuribayashi had under his command a force totaling between 21,000 and 23,000 men, including both Army and Navy units.

Lines of defense

General Kuribayashi made several changes in his basic defense plan in the months preceding the American invasion of Iwo Jima. The final strategy, which became effective in January 1945, called for the creation of strong, mutually supporting positions which were to be defended to the death. Neither large scale counterattacks, withdrawals, nor banzai charges were contemplated. The southern portion of Iwo in the proximity of Mount Suribachi was organized into a semi-independent defense sector. Fortifications included casemated coast artillery and automatic weapons in mutually supporting pillboxes. The narrow isthmus to the north of Suribachi was to be defended by a small infantry force. On the other hand this entire area was exposed to the fire of artillery, rocket launchers, and mortars emplaced on Suribachi to the south and the high ground to the north.

A main line of defense, consisting of mutually supporting positions in depth, extended from the northwestern part of the island to the southeast, along a general line from the cliffs to the northwest, across Motoyama Airfield No. 2 to Minami village. From there it continued eastward to the shoreline just south of Tachiiwa Point. The entire line of defense was dotted with pillboxes, bunkers, and blockhouses. Colonel Nishi's immobilized tanks, carefully dug in and camouflaged, further reinforced this fortified area, whose strength was supplemented by the broken terrain. A second line of defense extended from a few hundred yards south of Kitano Point at the very northern tip of Iwo across the still uncompleted Airfield No. 3, to Motoyama village, and then to the area between Tachiiwa Point and the East Boat Basin. This second line contained fewer man-made fortifications, but the Japanese took maximum advantage of natural caves and other terrain features.

As an additional means of protecting the two completed airfields on Iwo from direct assault, the Japanese constructed a number of antitank ditches near the fields and mined all natural routes of approach. When, on 2 January, more than a dozen B-24 Liberator bombers raided Airfield No. 1 and inflicted heavy damage, Kuribayashi diverted more than 600 men, 11 trucks, and 2 bulldozers for immediate repairs, rendering the airfield operational within only 12 hours. Eventually, 2,000 men were assigned the job of filling the bomb craters, with as many as 50 men detailed to one crater. By the end of 1944 American B-24 bombers were over Iwo Jima almost every night, and U.S. Navy carriers and cruisers frequently sortied into the Ogasawaras. On 8 December 1944, American aircraft dropped more than 800 tons of bombs on Iwo Jima, which did very little real damage to the island defenses. Even though frequent air raids interfered with the Japanese defensive preparations and robbed the garrison of badly-needed sleep, work was not materially slowed.

As early as 5 January 1945, Admiral Ichimaru conducted a briefing of naval personnel at his command post in which he informed them of the destruction of the Japanese Fleet at the Battle of Leyte Gulf, the loss of the Philippines, and the expectation that Iwo would shortly be invaded. Exactly one month later, Japanese radio operators on Iwo reported to the island commander that code signals of American aircraft had undergone an ominous change. On 13 February, a Japanese naval patrol plane spotted 170 American ships moving northwestward from Saipan. All Japanese troops in the Ogasawaras were alerted and occupied their battle positions. On Iwo Jima, preparations for the pending battle had been completed, and the defenders were ready.

American planning

U.S. Sixth Fleet during the invasion

The origins of the battle lie in the complex politics of the Pacific theater, in which operational control was divided between the South West Pacific Area (command) of General Douglas MacArthur and the Pacific Ocean Areas (command) led by Admiral Chester Nimitz. The potential for interservice rivalry between the Army and Navy created by this partition of responsibility was exacerbated by similar divisions within the Joint Chiefs of Staff (JCS) in Washington. By September 1944 the two services could not come to an agreement about the main direction of advance towards the Japanese home islands in the coming year. The Army was pressing for the chief effort to be an invasion of Formosa (Taiwan), in which MacArthur would be in overall command and in which it would predominate. The Navy however preferred the idea of an operation against Okinawa, which would be a mainly seaborne effort. Seeking to gain leverage and so break the impasse, on September 29 Nimitz suggested to Admiral Ernest King that as a preliminary to the Okinawa offensive the island of Iwo Jima could be taken. The tiny island lacked harbors and so was of no direct interest to the Navy, but for some time General Henry Harley Arnold of the U.S. Army Air Force had been lobbying to take Iwo Jima. He argued that an airbase there would provide useful fighter escort cover for the B-29 Superfortresses of his XX Bomber Command, then beginning its strategic bombing campaign against the Japanese home islands (the later role of Iwo Jima as a refueling station for B-29s played no part in the original decision-making process). Arnold's support in the JCS enabled the Navy to get Okinawa rather than Formosa approved as the main target on October 2. At this time the Iwo Jima invasion was expected to be a brief prologue to the main campaign, with relatively light casualties; King assumed that Nimitz would be able to reuse three of the Marine Corps divisions assigned to Iwo Jima for the attack on Okinawa, which was originally scheduled to take place just forty days later.

On 7 October 1944 Admiral Chester Nimitz and his staff issued a staff study for preliminary planning, which clearly listed the objectives of Operation Detachment. The overriding purpose of the operation was to maintain unremitting military pressure against Japan and to extend American control over the Western Pacific. Three tasks specifically envisioned in the study were the reduction of enemy naval and air strength and industrial facilities in the home islands; the destruction of Japanese naval and air strength in the Bonin Islands, and the capture, occupation, and subsequent defense of Iwo Jima, which was to be developed into an air base. Nimitz's directive declared that "long range bombers should be provided with fighter support at the earliest practicable time", and as such Iwo Jima was "admirably situated as a fighter base for supporting long range bombers."

On 9 October, General Holland Smith received the staff study, accompanied by a directive from Admiral Nimitz ordering the seizure of Iwo Jima. This directive designated specific commanders for the operation. Admiral Raymond A. Spruance, Commander, Fifth Fleet, was placed in charge as Operation Commander, Task Force 50. Under Spruance, Vice Admiral Richmond Kelly Turner, Commander, Amphibious Forces, Pacific, was to command the Joint Expeditionary Force, Task Force 51. Second in command of the Joint Expeditionary Force was Rear Admiral Harry W. Hill. General Holland Smith was designated Commanding General, Expeditionary Troops, Task Force 56.

It was not accidental that these men were selected to command an operation of such vital importance that it has since become known as "the most classical amphibious assault of recorded history." All of them had shown their mettle in previous engagements. One chronicler of the Iwo Jima operation put it in the following words:

"The team assigned to Iwo Jima was superb: the very men who had perfected the amphibious techniques from the Battle of Guadalcanal to the Battle of Guam. Nearly every problem, it was believed, had been met and mastered along the way, from the jungles of Guadalcanal up through the Solomons, and across the Central Pacific from the bloody reefs of Battle of Tarawa to the mountains of the Marianas."

Primary plan

American landing plan

The U.S. V Amphibious Corps scheme of maneuver for the landings was relatively simple. The 4th and 5th Marine Divisions were to land abreast on the eastern beaches, the 4th on the right and the 5th on the left. When released to VAC, the 3rd Marine Division, as Expeditionary Troops Reserve, was to land over the same beaches to take part in the attack or play a defensive role, whichever was called for. The plan called for a rapid exploitation of the beachhead with an advance in a northeasterly direction to capture the entire island. A regiment of the 5th Marine Division was designated to capture Mount Suribachi in the south. (map of the plan)

The detailed scheme of maneuver for the landings provided for the 28th Marine Regiment of the 5th Marine Division, commanded by Colonel Harry B. Liversedge, to land on the extreme left of the corps on Green 1. On the right of the 28th Marines, the 27th Marine Regiment, under Colonel Thomas A. Wornham, was to attack towards the west coast of the island, then wheel northeastward and seize the O-1 Line. Action by the 27th and 28th Marines was designed to drive the enemy from the commanding heights along the southern portion of Iwo, simultaneously securing the flanks and rear of VAC. As far as the 4th Marine Division was concerned, the 23rd Marine Regiment, commanded by Colonel Walter W. Wensinger, was to go ashore on Yellow 1 and 2 beaches, seize Motoyama Airfield No. 1, then turn to the northeast and seize that part of Motoyama Airfield No. 2 and the O-1 Line within its zone of action. After landing on Blue Beach 1, the 25th Marine Regiment, under Colonel John R. Lanigan, was to assist in the capture of Airfield No. 1, the capture of Blue Beach 2, and the O-1 Line within its zone of action. The 24th Marine Regiment, under Colonel Walter I. Jordan, was to be held in 4th Marine Division reserve during the initial landings. The U.S. 26th Marine Regiment, led by Colonel Chester B. Graham, was to be released from corps reserve on D-Day and prepared to support the 5th Marine Division.

Division artillery was to go ashore on order from the respective division commanders. The 4th Marine Division was to be supported by the 14th Marine Regiment, commanded by Colonel Louis G. DeHaven; Colonel James D. Wailer's 13th Marine Regiment was to furnish similar support for the 5th Marine Division.

The operation was to be timed so that at H-Hour 68 Landing Vehicle Tracked, comprising the first wave, were to hit the beach. These vehicles were to advance inland until they reached the first terrace beyond the high-water mark. The armored amphibians would use their 75 mm howitzers and machine guns to the utmost in an attempt to keep the enemy down, thus giving some measure of protection to succeeding waves of Marines who were most vulnerable to enemy fire at the time they disembarked from their LVTs. Though early versions of the VAC operations plan had called for tanks of the 4th and 5th Tank Battalions to be landed at H plus 30, subsequent studies of the beaches made it necessary to adopt a more flexible schedule. The possibility of congestion at the water's edge also contributed to this change in plans. In the end, the time for bringing the tanks ashore was left to the discretion of the regimental commanders.

Alternate plan

Since there was a possibility of unfavorable surf conditions along the eastern beaches, VAC issued an alternative plan on 8 January 1945, which provided for a landing on the western beaches. However, since predominant northerly or northwesterly winds caused hazardous swells almost continuously along the southwest side of the island, it appeared unlikely that this alternative plan would be put into effect.

The Battle of Iwo Jima

Ground fighting on the island took place over approximately 35 days, lasting from the landings of February 19th to a final Japanese charge the morning of March 26th, 1945.

Initial landings

U.S. Marines landing on Iwo Jima

At 02:00 on February 19, battleship guns signaled the commencement of D-Day. Soon 100 bombers attacked the island, followed by another volley from the naval guns. Although the bombs were consistent, it didn't deter the Japanese's defenses, as most of the Japanese positions were very well fortified and protected from shelling. At 08:59, one minute ahead of schedule, the first of an eventual 30,000 Marines of the 3rd, 4th, and 5th Marine Divisions, under V Amphibious Corps, landed on the Japanese island of Iwo Jima.

The initial wave was not hit by Japanese fire for quite some time, as it was the plan of Japanese General Kuribyashi to hold fire until the beach was full of American marines. Only after the front wave of Marines reached a line of Japanese bunkers defended by machine gunners did they take hostile fire.

Aside from the Japanese defenses situated on the actual "beaches", the Marines faced heavy fire from Mount Suribachi at the south of the island. It was extremely difficult for the Marines to advance due to the inhospitable terrain, which consisted of volcanic ash. This ash allowed for neither a secure footing nor the construction of defensive foxholes to protect the Marines from hostile fire. Yard by yard, the Marines advanced while taking heavy firearm and artillery fire. Thanks to the arrival of armored units and heavy naval artillery and air units shelling Suribachi, the Marines were eventually able to advance past the beaches. By that evening the mountain had been surrounded and 30,000 Marines had landed. About 40,000 more would follow.

In the days after the landings, the Marines expected a banzai attack during the night. This had been the standard Japanese defense strategy in previous battles against enemy ground forces in the Pacific, during which the majority of the Japanese attackers would be killed and the Japanese strength greatly reduced. However Kuribayashi had strictly forbade any banzai charges as he knew the futility of it.

Taking Mt. Suribachi

U.S. 37 mm gun fires against the Japanese cave positions

By the morning of the fourth day of the battle, Mount Suribachi was effectively cut off from the rest of the island—above ground. By that point, the Marines knew that the Japanese defenders had an extensive network of below-ground defenses, and knew that in spite of its isolation above ground, the volcano was still connected to Japanese defenders via the tunnel network. They expected a fierce fight for the summit.

Two four-man patrols were sent up the volcano to reconnoiter routes on the mountain's north face. Popular legend (embroidered by the press in the aftermath of the release of the now-famous photo "Raising the Flag on Iwo Jima") has it that the Marines fought tooth and nail all the way up to the summit. But although the riflemen were tensed for an ambush, none materialized. The riflemen did encounter small bodies of Japanese defenders on Suribachi, but the majority of the Japanese troops stayed underground in the tunnel network. The Japanese knew the importance of the flag. They attacked in small numbers, but all attackers were killed. They made it to the summit and scrambled down again, reporting the lack of enemy contact to Colonel Chandler Johnson.

Johnson then called for a platoon of Marines to climb Suribachi. With them, he sent a small American flag to fly if they reached the summit. Again, Marines began the ascent, expecting to be ambushed at any moment. And again, the Marines reached the top of Suribachi without incident. Using a length of pipe they found among the wreckage atop the mountain, the Marines hoisted the U.S flag over Mount Suribachi, the first foreign flag to fly on Japanese soil in centuries.

As the flag went up, Secretary of the Navy James Forrestal had just landed on the beach at the foot of Mt. Suribachi. He decided that he wanted the flag as a souvenir. Popular legend has it that Colonel Johnson wanted the flag for himself; in fact, he believed that the flag belonged to the 2nd Battalion, 28th Marines, who had captured that section of the island. He sent Sergeant Mike Strank (who was photographed in the Flag Raising picture) to scrounge up a second flag, and sent that one up the volcano to replace the first. As the first flag came down, the second went up, and it was then that Associated Press photographer Joe Rosenthal took the famous photograph "Raising the Flag on Iwo Jima" of the replacement flag being planted on the mountain's summit.

After Mount. Suribachi

Several M4A3 Sherman tanks equipped with flamethrowers were used to clear Japanese bunkers

Despite the loss of Mt. Suribachi, the Japanese still held a strong position. Kuribayashi still had the equivalent of eight infantry battalions, a tank regiment, two artillery and three heavy mortar battalions, plus the 5,000 gunners and naval infantry. The struggle to take the Motoyama Plateau, including "Turkey Knob" was to take the better part of three weeks. The Japanese actually had the Marines outgunned in this area, and the extensive tunnels allowed the Japanese to reappear in areas thought "safe".

The fighting was extremely fierce. Japanese troops would occasionally spring out of tunnels and ambush the Marines. However, the situation heavily favored American victory despite the Japanese advantage of superior firepower. Though the Marines occasionally encountered defensive positions augmented by artillery, they were still able to advance. The Marines learned that firearms were relatively ineffective against the Japanese defenders and learned to effectively use flamethrowers and grenades to flush out Japanese troops in the tunnels. One of the technological innovations of the battle, the 8 Sherman M4A3R3 medium tanks equipped with the Navy Mark I flame thrower ("Ronson" or Zippo Tanks), proved very effective at clearing the Japanese positions.

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 D+15. Similarly, illumination rounds (flares) which were used to light up the battlefield at night were initially provided by ships, shifting over later to landing force artillery. Navajo code talkers were part of the American ground communications, along with walkie-talkies and SCR-610 backpack radio sets.

Japanese troops became desperate towards the end of the battle. Kuribayashi, who had advocated against banzai attacks at the commencement of the battle, began to realize that Japanese defeat was inevitable. Marines began to face increasing amounts of nighttime attacks; these were only repelled by a combination of machine gun defensive positions and artillery support. In some cases, there was abundant hand-to-hand fighting before the Japanese were repelled.

Final days of the Battle

U.S. Marine Browning M1917 machine gun firing at the Japanese

With the landing area secure, more troops and heavy equipment came ashore and the invasion proceeded north to capture the airfields and the remainder of the island. Most Japanese soldiers fought to the death. On the night of 25 March, a 300-man Japanese force launched a final counterattack in the vicinity of Airfield Number 2. Army pilots, Seabees and Marines of the 5th Pioneer Battalion and 28th Marines fought the Japanese force until morning but suffered heavy casualties—more than 100 killed and another 200 American wounded.

Although still a matter of speculation due to conflicting accounts from surviving Japanese veterans, it has been said that Kuribayashi himself led this final assault which unlike the loud banzai charge of previous battles, was characterised as a 'silent' attack. If ever proven true, Kuribayashi will have been the highest ranking Japanese officer to ever personally lead an attack during World War II. Additionally, this would also be Kuribayashi's final act of departure from the normal practice of the commanding Japanese officers committing seppuku behind the lines while the rest perished in the banzai charge, as what happened during the battles of Saipan and Okinawa. Of all the Japanese that fought, 20,703 were killed and 216 were captured. As all the civilians had been evacuated, there was not one single civilian casualty at Iwo Jima, unlike at Saipan and Okinawa. The island was officially declared "secure" the following day.

According to letters written by Japanese soldiers who had served on Iwo Jima and had survived to the very last days of the fighting, Kuribayashi ordered his aide to cut off his head as a part of the Japanese suicide ritual, but the aide was killed by an American sniper before he could finish the job. Kuribayashi then shot himself with a pistol that had been presented to him during a visit to the United States of America before the war broke out. His body was buried by a Japanese soldier named Saigo and was never found.

Aftermath

U.S. Marines with a captured Japanese flag on Iwo Jima

"Among the men who fought on Iwo Jima, uncommon valor was a common virtue"—Admiral Chester W. Nimitz

Of the over 22,000 Japanese soldiers, 20,703 died and 216 were captured. Most of the Japanese actually killed themselves before they would've been captured or killed by the Americans.The Allied forces suffered 27,909 casualties, with 6,825 killed in action. Thus, the Allied forces suffered more casualties (dead plus injured) than their Japanese opponents.

After Iwo Jima was declared secured, the Marines estimated there were no more than three hundred Japanese left alive in the island's warren of caves and tunnels. In fact, there were close to three thousand. The Japanese bushido code of honor, coupled with effective propaganda which portrayed American G.I.'s as ruthless animals, prevented surrender for many Japanese soldiers. Those who could not bring themselves to commit suicide hid in the caves during the day and came out at night to prowl for provisions. Many did eventually surrender, and were surprised that the Americans often received them with compassion, offering water, cigarettes, or coffee. The last of these stragglers, two of Lieutenant Toshihiko Ohno's men, Yamakage Kufuku and Matsudo Linsoki, lasted six years, surrendering in 1951 (another source gives the date of surrender as January 6, 1949).

Over a quarter of the Medals of Honor awarded to Marines in World War II were given for conduct in the invasion of Iwo Jima. The Marines, both active duty and reservists, were commended with 22 Medals of Honor. An additional five Medals of Honor were bestowed upon five Navy servicemen and reservists.

Dinah Might surrounded by Marines and Seabees after emergency landing on Iwo Jima

Given the amount of casualties, the necessity and long-term significance of the island's capture to the outcome of the war was a contentious issue from the beginning, and remains disputed. As early as April 1945 retired Chief of Naval Operations William V. Pratt asked in Newsweek magazine about 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 Japanese on Iwo Jima had radar with which they notified their comrades at home of incoming B-29s flying from the Marianas. Fighter aircraft based on Iwo Jima sometimes attacked these planes, which were especially vulnerable on their way to Japan because they were heavily laden with bombs and fuel. The island was also used as an air-sea rescue base after its seizure. However, the traditional justification for Iwo Jima's strategic importance to the United States' war effort has been that it provided a landing and refueling site for American bombers on missions to and from Japan. As early as March 4, 1945, while fighting was still taking place, the B-29 bomber 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, without incident, and was serviced, refueled and departed. In all, 2,251 B-29 Superfortresses landed on Iwo Jima during the war.

None of these calculations played much if any of a role in the original decision to invade, however, which was almost entirely based on the Army Air Force's belief that the island would be a useful base for long-range fighter escorts. For a number of technical reasons these escorts proved both impractical and unnecessary, and only ten such missions were ever flown from Iwo Jima. Other justifications are also debatable. Although some Japanese interceptors were based on Iwo Jima, their impact on the American bombing effort was marginal; in the three months before the invasion only 11 B-29s were lost as a result . The Superfortresses found it unnecessary to make any major detour around the island. 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 attacked). Some downed B-29 crewmen were saved by air-sea rescue aircraft and vessels operating from the island, but Iwo Jima was only 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, USMC Captain Robert Burrell of the US Naval Academy has suggested that only a small proportion of the 2,251 landings were for genuine emergencies, the great majority being for minor technical checkups, training, or refueling. According to Burrell, "this justification became prominent only after the Marines seized the island and incurred high casualties. The tragic cost of Operation Detachment pressured veterans, journalists, and commanders to fixate on the most visible rationalization for the battle. The sight of the enormous, costly, and technologically sophisticated B-29 landing on the island's small airfield most clearly linked Iwo Jima to the strategic bombing campaign. As the myths about the flag raisings on Mount Suribachi reached legendary proportions, so did the emergency landing theory in order to justify the need to raise that flag."

The United States Navy has commissioned several ships of the name USS Iwo Jima.

The USMC War Memorial outside Washington, D.C. memorializes all U.S. Marines with a statue of the famous picture.

Reunion of Honor

Memorial on the top of Mt. Suribachi

2005 Reunion of Honor

On February 19, 1985, an event called the "Reunion of Honor" was held. It was on this day in 1945 when U.S. forces invaded Iwo Jima.

The ex-soldiers of both sides who fought in the battle of Iwo Jima, attended the event. The place was the invasion beach where U.S. forces landed. A monument on which writings were engraved by both sides was built at the center of the meeting place. Japanese attended at the mountain side, where the Japanese writing was carved, and Americans attended at the shore side, where the English writing was carved. After unveiling, and offering of flowers were made, the representatives of both countries approached the monument; upon meeting, they shook hands. The old soldiers embraced each other and cried.

The combined Japan-U.S. memorial service of the 50th anniversary of the battle was held in front of this monument on March, 1995. Further memorial services have been held on later anniversaries.