The Battle of Iwo Jima (February to March 1945) was the bloodiest battle of WWII's Pacific War. A 72-day bombing campaign pounded the island before 110,000 US Marines landed on the beaches. The Japanese defenders had dug themselves a bewildering maze of bunkers, tunnels, and pillboxes, which made clearing the island a deadly business. The US forces won the battle after 36 days of intense fighting but suffered over 27,000 casualties. From the Japanese garrison of 21,000, only 216 men survived the battle. The prize of victory was a strategically important island that could now be used to launch fighter planes to escort the heavy bombers already flying from the Mariana Islands and hitting the main Japanese islands.
The Pacific War So far
The Japanese military government had built an impressive empire for itself, which, by 1941, spread from northern China to the Solomon Islands. In December 1941, Japan, seeking to crush its enemy before it had a chance to even enter the war, launched the infamous attack on Pearl Harbor, the US naval base in Hawaii. The US responded powerfully, sending its navy to the Battle of the Coral Sea in May 1942, winning the Battle of Midway the following June, freeing the Solomon Islands in the Guadalcanal Campaign (August 1942 to February 1943), and following all that up with another victory in the Gilbert and Marshall Islands Campaign (November 1943 to February 1944).
The US forces were now 'island-hopping' across the Pacific, each time using a captured island group to build a new base from which another amphibious advance could be made; Japan went on the defensive. US forces targeted the Mariana Islands in the Battle of Saipan (Jun-Jul 1944) and the Battle of Guam (Jul-Aug). In between, a resounding victory crushed the Imperial Japanese Navy in the Battle of the Philippine Sea. Admiral Chester W. Nimitz (1885-1966), Commander-in-Chief of the US Pacific Fleet, set up his headquarters on Guam, and from here, he would direct the rest of the Pacific campaign. Moving ever closer to the Japanese home islands, the next major encounter came at Iwo Jima.
If the US forces could capture Iwo Jima, they could create an air base to greatly increase the ongoing strategic bombing of Japan. Further, with Tokyo only three hours flying time from the island, the Boeing B-29 Superfortress bombers flying out from the Marianas could enjoy a fighter escort throughout their mission over the skies of Japan. On the other hand, continued Japanese possession of Iwo Jima would mean their fighters could intercept those same B-29s long before they ever got to Japan. Iwo Jima also had a Japanese radar station, which, being on the flight path of the B-29s, was relaying warnings back to Tokyo. In short, Iwo Jima was vital for both Japan and the United States, and the battle for control of it would dictate the next phase of the war.
Iwo Jima
Iwo Jima, an active volcanic island the shape of a pear, measures just 5 miles (8 km) in length. It is located 650 miles (1,045 km) from Tokyo. Then part of Japan's inner ring of defences, Iwo Jima had three airstrips (although one was still under construction). The rugged landscape of ravines, rock ridges, and cave systems is dominated by Mount Suribachi, which rises some 550 feet (168 m) above sea level at the southern end of the island. The civilian population had already been evacuated by the time the battle started.
The task of taking Iwo Jima was given to the 4th and 5th Marine Divisions of the 5th Amphibious Corps. The 3rd Marine Division would act as a reserve. The amphibious assault, code-named Operation Detachment, would be led by Major-General Harry Schmidt (1886-1968). 800 naval ships were involved in the operation, and a total of 110,000 men would be put on the island. The US military planners predicted just 14 days would be needed to take the island. As so often before in this war, the difference between looking at a map and actually fighting in jungle terrain against an often suicidal enemy was a stark one. It would, in fact, take 36 days to conquer Iwo Jima.
The Amphibious Assault
Before the amphibious operation got underway on 19 February, the US air force bombarded the island for 72 days. The final 72 hours of the attack were joined by the heavy guns of all kinds of naval ships, from destroyers to battleships, although this extra barrage was hampered by poor weather conditions. Unfortunately for the US amphibious force, the shells and bombs did little damage to the well-situated and often wholly submerged bunkers of the defenders.
Bizarrely, the first 20 minutes of the invasion passed without any fire at all from the defenders. The Marines must have hoped the bombing campaign had actually done what the commanders promised it had and destroyed the Japanese gun positions completely. Then reality struck as all hell broke loose.
The two beaches of the landings – located in the southeast of the island – were hit relentlessly and accurately by the Japanese artillery (which was aided by spotters on the higher ground), pinning the Marines down. The defensive fire created havoc with the amphibious vehicles, which caused a logjam and blocked more vehicles landing more men, not to mention the vehicles transporting the wounded going the other way also blocking the seaways. The volcanic nature of the beaches did not help the speed of progress either; the Marines often sank knee-deep in the soft ash, and then they struggled to get over the sloping high ridges that barred access to the inland terrain. As Marine Corpsman Herman Rabeck remembered:
As you hit the island it was – if there's ever been hell, this was it. There wasn't a living thing anywhere in sight. I would say that forty to fifty per cent of the men I got close to were dead…There was a little incline and everybody clung to the incline because the fire was that heavy and everything that hit the beach was blasted out of the water as fast as it hit it.
(Holmes, 488)
Casualties were extremely high amongst the first waves of men tasked with carving out a beachhead. This was despite the use of innovative LVTs (Landing Vehicles, Tracked) armed with either one 75-mm (2.95-inch) howitzer or two 20-mm (0.8-inch) cannons. The US Navy helped with a 'creeping' barrage that steadily moved inland, reducing the Japanese fire upon the beaches, and bulldozers created roadways through the beach ridges. Gradually, the Marines, supported by tanks, were able to push on from the beachheads.
Kuribayashi's Defence
Defence of the island was the responsibility of Lieutenant General Tadamichi Kuribayashi (1891-1945), and he commanded a garrison of around 21,000 men. The island had been steadily reinforced ever since March 1944. Kuribayashi knew the absolute necessity of defending Iwo Jima and had informed his wife before being sent there: "Do not plan for my return" (Wright, 10).
The general had his men set up flanking fire on the advancing enemy on the beaches, which was very effective and took full advantage of the congestion of troops and vehicles there. Kuribayashi, though, kept most of his force in reserve, knowing that the real battle of attrition would be fought in the island's interior. In any case, the sheer weight of numbers – a hugely impressive 30,000 men had been landed on the first day – and the courage of the Marines ensured the beaches were taken and the first airstrip was captured on day two of the operation.
By day five, the second airstrip was captured, and Mount Suribachi was assailed. The raising of a large US flag on Mount Suribachi by a group of Marines (actually a second attempt after a smaller flag had been raised a few hours before, but not, as myth would have it, staged) was photographed by Joe Rosenthal. The photograph became one of the iconic images of WWII and was seen everywhere from posters to postage stamps. But the real work was yet to come.
Kuribayashi had at his disposal, besides the infantry, several battalions of anti-aircraft guns, mortars, cannons, and machine gunners. There was a tank regiment, an artillery brigade, and engineering groups to design the defences. The intense and prolonged bombing campaign had only driven the defenders to dig even deeper bunkers and tunnel systems in which to hide. Korean labourers had been shipped in months before to prepare these defences.
The soft pumice-like volcanic rock was easily cut with hand tools and mixed well with cement to provide excellent reinforcement. Some tunnel were 75ft (23m) under ground, most were interconnecting, and many were provided with electric or oil lighting. Supply points, ammunition stores, and even operating theatres were included in the system…
(Wright, 18)
As in other battles in the Pacific campaign, the Japanese soldiers believed surrender was dishonourable and so fought to the death. Marine Sergeant Wilson Cook describes the difficulties and dangers of ferreting out determined Japanese defenders:
We used everything available – demolition charges, flame-throwers and what not – but the Japanese were so well entrenched and had been there for so many months preparing the islands for defensive situations that if you blew one entrance another would open up, and they had tools inside with which to work themselves back to the surface. They had sliding doors to close off so that the flame-throwers wouldn't get them and exhaust the oxygen. So it meant simply that men went in, active men, and you killed them underground. It was just rough.
(Holmes, 483)
The progress was slow and deadly. Tanks, flame-throwing armoured vehicles (known to the troops as "Zippos" after the famous lighter manufacturer), and armoured bulldozers proved much more effective against the well-prepared Japanese positions than artillery fire, although this still rained down anyway, supported by US naval and air bombardments and teams of rocket-firing trucks on the ground. The only effective way to deal with each enemy position was to attack it with napalm, flamethrowers, and TNT explosives. The death toll from such brutal and often hand-to-hand fighting was outrageously high. Sergeant Cooke remembers: "…we stayed committed for twenty-six days…I have a picture taken on Iwo of my company. There's sixteen of us left out of two hundred and seventy that went in" (Holmes, 487).
Such heavy casualties meant that very often officers were killed and so command of a group of men passed down from a captain to a lieutenant to a sergeant, and even sometimes to a Private First Class. Replacements were often poorly trained and unable to use even the most basic equipment like heavy machine guns. Some battalions were entirely wiped out, including their reinforcements. Meanwhile, some Japanese aircraft attempted to drop ammunition, food, and medical supplies by parachute, but the US dominated the skies, and most were shot down before they could deliver their relief. In contrast, a bakery set up behind the lines was able to serve coffee and doughnuts to beleaguered Marines.
The end of this terrible battle was near, but even when they seemingly surrendered, Japanese troops would often blow themselves up and their captors using grenades. One particular group of fortifications, officially called Hill 382, was renamed 'The Meat Grinder' by the US troops because so many men died trying to take it. Again, as seen in other battles, the remaining Japanese soldiers made one final, desperate, and suicidal banzai charge, so called from the battle cry Tenno heika banzai ('Long Live the Emperor'). This final action occurred in a canyon that quickly became known as 'Bloody Gorge'. Incredibly, the canyon was a mere 700 yards (650 m) in length, but it took ten days of bitter fighting before the Marines could, on 26 March, claim they had won a total victory.
US losses at the Battle of Iwo Jima were 8,700 men killed and 19,000 wounded. With the exception of 216 men who surrendered, the 21,000 members of the Japanese garrison were wiped out (Holmes, 488). Marine Lieutenant General Holland Smith described the battle as "the toughest we've run across in 168 years" (Horner, 64). The Pacific War historian D. Marston agrees, noting that Iwo Jima was "the bloodiest battle in Marine Corps history and the only landing in which the Japanese inflicted more casualties on their enemy than they suffered themselves" (172). Admiral Nimitz noted that "Among the Americans who fought on Iwo Jima, uncommon valor was a common virtue" (Wright, 10). 27 Medals of Honour were awarded for valour during the course of the battle.
Aftermath
By the first week of April, Iwo Jima's airstrips were being used to launch North American P-51 Mustang fighters to escort B-29 bombing raids against Japan. The island also became a very useful insurance option for aircraft flying from further south such as Guam, Tinian, and Saipan. "By the end of the war over 2,000 B-29s had made successful emergency landings on Iwo Jima [otherwise they would have been lost in the sea], and the 24,000 crew members they carried thereby escaped death or injury" (Smurthwaite, 128).
The next island to be taken was Okinawa in the Ryukyu Islands in April 1945. The Battle of Okinawa, the last major one of the war, resulted in up to 100,000 Japanese soldiers killed, with around 38,000 US troops wounded and around 12,000 killed (National Museum of the Pacific War). Even in defeat, then, the Japanese military continued to inflict unacceptably heavy casualties on US forces. Finally, the terrible destruction of Hiroshima and Nagasaki in August using nuclear bombs avoided the need for further amphibious operations and, at last, brought Japan's surrender.
