The Battle of Iwo Jima
Name of Event: “Battle of Iwo Jima”
Date of Event: 19 February – 26 March 1945
Location: Iwo Jima, Volcano Islands (Pacific)
Participants: United States and Japanese Empire
Outcome: American Victory
The Battle of Iwo Jima occurred on 19 February 1945 as United States Marines faced off with Japanese defenders on the tiny volcanic island of Iwo Jima during World War Two. The invasion was one of the fiercest battles of the war, as Japanese troops refused to surrender to American forces during the fighting, resulting in substantial losses for both sides of the conflict.
Although the strategic importance/value of Iwo Jima has often been debated (and contested) by scholars and historians, alike, the victory proved to be hugely demoralizing for the Japanese Empire as the island’s capture placed American troops within 760 miles of the Japanese mainland.
Strategic Importance of Iwo Jima
Iwo Jima was a critical base of operations for the Japanese Empire due to its strategic proximity to the Japanese mainland. Only 760 miles from the southern tip of Japan, Iwo Jima offered the Japanese Empire a critical airbase that could be used to intercept American B-29 Superfortress Bombers on their approach to the mainland, and to stage air raids against the Mariana Islands. It also provided the Japanese with a naval base for both refueling and resupply.
American interest in the island was three-fold, as they believed that the capture of Iwo Jima would not only end air raids against the Marianas, but would also help protect American bombers and serve as a strategic location to stage “Operation Downfall” (the planned invasion of the Japanese mainland). With the capture of Iwo Jima, the Americans could also cut the distance of B-29 air raids on Japan in half, and provide the B-29s with fighter escort from the short-ranged P-51 Mustang fighter aircraft.
In addition to these strategic values, American intelligence was also confident that the island would be easy to capture, given the superior number of American forces and equipment compared to the Japanese defenses. Naval officers estimated that Iwo Jima could be captured within a week. Unbeknownst to American planners, however, the Japanese were well aware of American intentions, and had already began construction of a complex and strategic network of defenses that would prove extremely deadly for the Marine invaders.
Planning for the defense of Iwo Jima had already begun in June of 1944 under the command of Lieutenant General, Tadamichi Kuribayashi. Kuribayashi was well aware of American strength and knew that Iwo Jima would eventually fall. He was also well-aware that an invasion of the Japanese mainland was imminent given the rapid advances of the American military along the Pacific. For these reasons, Kuribayashi attempted to implement a defense grid across Iwo Jima that was designed to inflict massive casualties on the American forces. Kuribayashi hoped that a radical defense of the island would make the Allies reconsider an invasion of the Home Islands if he could inflict severe casualties on the invading force.
Kuribayashi’s plans for defense broke with traditional Japanese military doctrine on a number of specific points. Rather than establishing a defense force along the beach, as Japanese troops had done in earlier battles across the Pacific, Kuribayashi stationed much of his heavy weapons and machine gun emplacements further inland, using armored tanks as artillery pieces and pre-sighting vast areas of the beach for an artillery barrage on the expected Marine landing. Kuribayashi also used the formerly active volcano, Mount Suribachi, to his advantage by establishing a vast tunnel network inside the mountain to funnel troops and supplies to areas under direct attack.
For his main line of defense, Kuribayashi organized most of his forces along the northern sector of Iwo Jima. Through the construction of vast bunkers and pillboxes (some of which approached 90 feet in depth), Kuribayashi stocked each of these areas with enough supplies to hold out against the Marines for three months (including ammunition, kerosene, food, water, and gasoline).
Kuribayashi also implemented a vast network of mortars and land mines across the island, along with numerous positions for rockets. Sniper positions were also established across strategic points on Iwo Jima, along with numerous camouflaged machine gun positions.
Similar to their Japanese counterparts, the Americans also began their planning for Iwo Jima around June of 1944, and began strategic naval and air bombardments of the island for several months prior to the planned invasion. For nine months, the U.S. Navy and Army Air Forces conducted lightning-fast raids on the island, albeit with limited success (due to the number of reinforced bunkers that were developed by the Japanese defenders). Two days before the planned invasion, the U.S. Navy also deployed Underwater Demolition Team 15 (UDT-15) along Blue Beach to recon the area and destroy any landmines they encountered. The team was spotted by Japanese infantry, however, which resulted in a massive firefight that resulted in the death of one American diver (and an unknown number of Japanese).
As the planned invasion day approached, American officers believed that the island would be easy to take given the months of strategic bombing that had been carried out against the island’s defenses. American planners, however, were unaware of Kuribayashi’s strategic tunnel network that had been implemented for such attacks. Naval and air bombardment, including the three-day shelling of the island (just prior to the invasion) did little in regard to the destruction of Japanese defenses which remained largely intact.
On the night of 19 February 1945, Vice Admiral Marc Mitscher’s “Task Force 58” (a huge carrier battle group) arrived off the coast of Iwo Jima. At 08:59 hours, the first wave of Marines were launched from the ships offshore to begin their amphibious landing along the southeastern shore of Iwo Jima. To everyone’s surprise, the landing began badly for the Marines as American military planners had failed to take into account the fifteen-foot-high slopes of volcanic ash that lined Iwo Jima’s southern shore. After hitting the beach, the Marines could neither dig in, nor construct foxholes to evade enemy fire, leaving them exposed to Japanese attack. The soft ash also made it extremely difficult to move forward, as the Marines found walking on the ash-like surface difficult to tread upon.
The lack of response (initially) by the Japanese defenders created a sense of euphoria amongst the Navy and Marines who erroneously believed that days of bombardment had destroyed much of the Japanese Army’s defenses on Iwo Jima. On the contrary, the prolonged silence was part of a calculated plan by General Kuribayashi to allow the Marines to pile up on Iwo Jima’s beaches for a heavy artillery barrage from mortars and tanks. At approximately 10:00 hours (nearly an hour into the invasion), Kuribayashi instructed his men to unleash their machine guns and heavy artillery on the unsuspecting Marines, inflicting mass-casualties in the ensuing carnage. Using Mount Suribachi as a strategic high-ground, the Japanese also began to fire artillery from their vast tunnel networks, which allowed them to fire and retreat before American naval support could return fire and destroy them.
As the situation looked dire for the Marines, the U.S. Army’s 147th Infantry Regiment was dispatched to scale a ridge approximately 0.75 miles from the base of Mount Suribachi to provide fire on enemy positions that were hammering the Marine units. Although the move was successful in its diversion of enemy fire away from the beach, the 147th soon found itself in some of the fiercest fighting experienced at Iwo Jima.
As the situation continued to deteriorate for the Marines along Iwo Jima’s southern shore, and with Amtracs (amphibious landing craft) unable to proceed up the beach due to the soft ash surface, the Marines were forced to move forward on foot, braving fierce enemy resistance. As the Marines reached the southern tip of Airfield Number One (a primary objective) by 11:30 hours, Naval Construction Battalions were able to use bulldozers to construct makeshift roads along Iwo Jima’s beaches, which allowed much-needed equipment and supplies to be brought ashore.
As Marine Colonel Harry Liversedge and his 28th Marines drove inland, other Marines faced fanatical banzai attacks by large groups of Japanese troops, forcing them to halt their advance on numerous occasions to set up defensive positions. However, by nightfall on 19 February, Colonel Liversedge and his Marines were able to isolate Mount Suribachi from the rest of Iwo Jima as their advance crippled supply lines to the ancient volcano.
Along the right flank of the Marine invasion, the 25th Marines attempted to dislodge enemy forces from an area known as the Quarry. Beginning with approximately 900 men, the Marines fought heroically against ferocious Japanese resistance. Although the Marines succeeded in pushing forward by nightfall along the right flank, they suffered an 83.3 percent casualty rate, as only 150 Marines were left out of their original group.
In total, nearly 30,000 Marines had hit the beach at Iwo Jima by nightfall on 19 February, with 40,000 additional Marines and Army troops on the way in the days that followed. For the command staff awaiting offshore, the first day of fighting along Iwo Jima had demonstrated not only the Japanese resolve in holding the island, but that initial American intelligence about Iwo Jima was very wrong. The fight would not be easy, and the island would not fall within a matter of days as planned.
After establishing a beachhead to land additional troops, Marine units began to expand their assault on Iwo Jima facing radical Japanese resistance in their forward movement. Due to the tunnel networks established by the Japanese defenders, the use of firearms often proved ineffective against the Japanese as only flamethrowers and grenades could penetrate the deep bunkers and flush out enemy forces. Close air support was also established for the Marines, as the 15th Fighter Group (P-51 Mustangs) provided continuous assaults across the island for the duration of the conflict.
Although Kuribayashi had strictly forbade the use of banzai attacks against the Marines, due to his belief that such assaults were a waste of precious lives and resources, sporadic banzai attacks were carried out against Marine forces in their assault, particularly at night when the Japanese could use the cover of darkness to advance. Such attacks, as Kuribayashi had predicted, however, proved futile, as Marine forces were well-prepared for banzai charges from their previous experiences of the war.
The Tide Turns
By 20 February, the first of Iwo Jima’s three airstrips were captured by Marine forces along the southern tip of Iwo Jima. By 23 February, the Marines were able to successfully capture Mount Suribachi, raising the American Flag upon its summit in what became one of the most spectacular photos to emerge from the Second World War. Atop Mount Suribachi, the raising of the American Flag could be seen by everyone on Iwo Jima, providing a huge boost of morale to American forces (and subsequently demoralizing the Japanese defenders who knew that defeat was inevitable). On the same day, Marine forces also managed to capture Iwo Jima’s second airfield as they continued to push north on the island.
As Japanese supplies began to dwindle dramatically, some of the heaviest fighting of the battle occurred along a position known by the Americans as Hill 382. Known as the “meatgrinder,” Japanese forces desperately committed themselves to defending the area against Marine forces. Refusing to surrender, the Japanese fought the Americans to the death, inflicting massive casualties on the Marines as they continued to move forward. By 1 March, however, the hill was cleared of all Japanese defenders.
"The raising of that flag on Suribachi means a Marine Corps for the next 500 years."— James Forrestal
With approximately 60,000 Marines on the island by the beginning of March, defeat for the Japanese was inevitable. However, Kuribayashi and his men refused to surrender and chose a rocky gorge along the northern sector of the island, known as “Bloody Gorge,” to stage a last-ditch defense of the island. With only a few hundred men remaining, Kuribayashi and his men held out against the Marines for ten days before finally being wiped out. By 16 March 1945, the island was officially declared as “secure” by the Marine and Navy high-command, thus, ending the bloody (and very costly) thirty-six day campaign.
Do you believe that Iwo Jima held a strategic value for the Americans?
In closing, the Battle of Iwo Jima was one of the fiercest battles of World War Two. Out of 21,000 Japanese defenders, it is estimated that only 200 Japanese soldiers were left alive on the island due to their refusal to surrender. For the Americans, Marine and Army losses are estimated to be approximately 6,800 dead, along with 19,200 wounded.
Following the battle, Iwo Jima’s strategic value was called into question by many high-ranking officials as neither the Army nor the Navy were able to use the island as a staging area for future attacks. Although Navy Seabees (construction battalions) were able to construct emergency airfields for B-29 pilots to use on return flights from Japan, the initial plans for Iwo Jima were largely scrapped by the Americans. Although heavy losses were inflicted on the Japanese at Iwo Jima, the cost in American lives was also tremendous, leading many scholars and historians to debate the overall effectiveness of a campaign against the island. Regardless of its strategic value, however, the assault (and defense) of Iwo Jima was far more than a battle; it represented the highest levels of selflessness, courage, and bravery amongst those who participated in the conflict, and should never be forgotten.
Wikipedia contributors, "Battle of Iwo Jima," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=Battle_of_Iwo_Jima&oldid=888073875 (accessed April 17, 2019).
Wikipedia contributors, "Raising the Flag on Iwo Jima," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=Raising_the_Flag_on_Iwo_Jima&oldid=892856897(accessed April 17, 2019).
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© 2019 Larry Slawson