Iwo Jima Tunnel System

IWO JIMA The United States strategy in the Pacific was known as island hopping. Key Japanese-held islands were captured, and air bases built. Each captured island became a steppingstone that brought us ever closer to the Japanese home islands. The territory controlled by Japan covered vast distances in the Pacific. Americans would not try to capture every Japanese-held island in the Pacific, only islands of strategic value. The cost in American lives would still be great. Iwo Jima was a tiny, volcanic island, only eight square miles in size. It lacked a source of fresh water and smelled like rotten eggs from high levels of sulfur on the island. Iwo Jima means “sulfur island” in Japanese. What strategic value did this rugged, smelly, volcanic island have? Iwo Jima was 660 miles southeast of Tokyo. It was an essential air base for bombing missions over Japan and as such it was heavily defended. American long-range B-29 bombers were already flying bombing raids over Japan, but these raids were being flown from such great distances that the situation produced many problems. Once the bombers were over their sites, they didn’t have enough fuel to adjust for winds or weather. Consequently, they frequently didn’t hit their targets. Planes damaged by enemy fire had no friendly airfield to land on. Furthermore, the two airfields on Iwo Jima were being used as a base for Japanese fighter planes to attack American planes. On February 19, 1945, the 4th and 5th Marine Divisions landed on Iwo Jima. Before their arrival, U.S. forces had bombarded the island with shells and bombs for more than 70 days. The Japanese were well dug in. Months before the arrival of U.S. forces, the Japanese commander on Iwo Jima, General Tadamichi Kuribayashi, had ordered his engineers to expand the island’s caves and build an intricate system of connecting caves and tunnels that included its own ventilation (fresh air) system and that hid Japanese gun positions. Camouflaged caves hidden from view, pillboxes and blockhouses covered the island. The Japanese soldiers, burrowed into hiding places, were invisible to the American Marines landing on the island on February 19. The USS North Carolina bombarding Japanese positions on Iwo Jima prior to the US landings. US Marines in landing craft speeding toward Iwo Jima. Mount Suribachi is seen in the distance. At first the Marines encountered almost no resistance. In a deathly silence, landed U.S. Marines began to slowly inch their way forward inland, oblivious to the danger. After allowing the Americans to pile up men and machinery on the beach for just over an hour, General Kuribayashi, the Japanese commander, unleashed the undiminished force of his countermeasures. Everything from machine guns and mortars to heavy artillery began to rain down on the crowded beach, which was quickly transformed into a nightmarish bloodbath. Time-Life correspondent Robert Sherrod described it simply as "a nightmare in hell.” He wrote: It began as a ragged rattle of machine-gun bullets, growing gradually lower and fiercer until at last all the pent-up fury of a hundred hurricanes seemed to be breaking upon the heads of the Americans. Shells screeched and crashed, every hummock spat automatic fire and the very soft soil underfoot erupted underfoot with hundreds of exploding land mines ... Marines walking erect crumpled and fell. Concussion lifted them and slammed them down, or tore them apart … Gradually, small groups of US troops inches their way forward. As they had made their way well inside the nest of the hidden enemy, the Japanese opened fire from caves and disguised pillboxes. The barrage of lethal fire cut marines in half. Surviving marines scrambled to take cover but found it impossible to dig into the island’s volcanic ash. Along with bullets, survivors were assaulted by the sickening smell of sulfur and decaying bodies. US troops landing on Iwo Jima in February of 1945. The battle lasted for five weeks and contained some of the most bloody and brutal fighting of the whole war. US troops pinned down on the beaches at Iwo Jima shortly after coming ashore. From the heights of Mount Suribachi, hidden Japanese guns raked machine gun and artillery fire on the marines. The Japanese heavy artillery in Mount Suribachi opened their reinforced steel doors to fire, and then closed them immediately to prevent counterfire from the Marines and naval gunners. This made it almost impossible for American units to destroy the Japanese artillery. To make matters worse for the Americans, the bunkers were connected to the elaborate tunnel system so that bunkers that were cleared by the Americans were reoccupied shortly afterwards by Japanese troops moving through the tunnels. This tactic caused many casualties among the Marines, as they walked past the reoccupied bunkers without expecting to suddenly take fresh fire from them. The 25th US Marine Regiment undertook a two-pronged attack to silence the heavy guns. For three days, Marines clawed and fought their way up the steep, pitted and smoldering slopes of Mount Suribachi. They were supported by a constant air and naval bombardment from the US invasion fleet. 2nd Lt. Benjamin Roselle, part of a ground team directing naval gunfire, wrote: Within a minute a mortar shell exploded among the group ... One of the men had his left foot and ankle hung from his leg, held on by a ribbon of flesh ... Within minutes a second round landed near him and fragments tore into his other leg. For nearly an hour he wondered where the next shell would land. He was soon to find out as a shell burst almost on top of him, wounding him for the third time in the shoulder. Almost at once another explosion bounced him several feet into the air and hot shards ripped into both thighs ... as he lifted his arm to look at his watch a mortar shell exploded only feet away and blasted the watch from his wrist and tore a large, jagged hole in his forearm: "I was beginning to know what it must be like to be crucified," he was later to say. The 25th Marines' 3rd Battalion had landed approximately 900 men. Japanese resistance was so fierce that in less than 3 days only 150 Marines were left fighting. To break the impasse, flamethrowers were brought in to burn out the unseen enemy. Sherman M4A3R3 medium tanks equipped with a flamethrower, known as "Ronson" or "Zippo" tanks, proved very effective at clearing Japanese positions. After fierce fighting, the ancient volcano, the highest point on the island, was eventually captured by the leathernecks on February 23. Associated Press photographer, Joe Rosenthal, snapped his famous picture of five marines and one navy corpsman raising the American flag at the top of Mount Suribachi. However, the battle for Iwo Jima was far from over. The Marines still had to capture the island’s two airfields. Before the island was taken, three of the flagraisers would die. A US 37 mm anti-tank gun fires against Japanese cave positions in the north face of Mount Suribachi. Marines torch a Japanese defensive in Iwo Jima’s Mount Suribachi by using flamethrowers. Flamethrowers were an effective weapon for burning out entrenched fighters who would have otherwise continued to fight, costing more lives. Despite Japan's 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 easier to hit with naval artillery fire. Coupled with this, the fortifications constructed by Kuribayashi were more impressive than 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. The most arduous task left to the Marines was the overtaking of the Motoyama Plateau with its distinctive Hill 382 and Turkey Knob and the area in between referred to as the Amphitheater. Fighting here came to be known as the "meatgrinder". Japanese positions were well-entrenched. Fighting was savage. The US Marines paid dearly in lives for every foot of ground taken. The 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, with American casualties piling up. Even capturing these points was not a solution to the problem since a previously secured position could be attacked from the rear by the use of the tunnels and hidden pillboxes. As such, it was said that "they could take these heights at will, and then regret it.” In the end, the Americans would finally prevail. Admiral Nimitz declared a victory on March 14, but the last pockets of enemy resistance were not cleared from the island until weeks later. The island was officially declared secure at 09:00 on March 26. The costly five-week battle saw some of the fiercest and bloodiest fighting of the Pacific War. Once the island was officially declared secure, however, Americans soon found themselves locked in a bitter struggle against thousands of stalwart defenders engaging in a last-ditch guerrilla campaign. Using well-supplied caves and tunnel systems, the Japanese resisted American advances. For three months, the Army's 147th Infantry Regiment, ostensibly there to act as a garrison, slogged across the island. Using flamethrowers, grenades, and satchel charges to dig out the enemy, they killed some 1,602 Japanese soldiers in small unit actions while suffering fifteen men killed in action and another 144 wounded. The M4A3R5 flamethrower seen here on Iwo Jima had a range of 150 yard. The Marines said that the flamethrowing tanks were the single best weapon they had in taking the island. ..athat they were the only thing the Japanese feared. The bloody battle for this small volcanic island was very costly. More than 6,000 Americans were killed and another 18,000 wounded. The Japanese combat deaths numbered three times the number of American deaths, but uniquely among Pacific War Marine battles, the American total casualties (dead and wounded) exceeded those of the Japanese. Of the 21,000 Japanese soldiers on Iwo Jima at the beginning of the battle, only 216 were taken prisoner, most of whom were captured only because they had been knocked unconscious or otherwise disabled. Most of the remainder were killed in action. As many as 3,000 continued to resist within the various cave systems for many days afterwards until they eventually succumbed to their injuries or surrendered weeks later. Unbelievably, the last of Japanese holdouts on the island, Yamakage Kufuku and Matsudo Linsoki, lasted four years without being caught and did not surrender until January 6, 1949. Despite the fighting and severe casualties on both sides, the American victory was assured from the start. Overwhelming American superiority in numbers and arms as well as air supremacy, coupled with the impossibility of Japanese retreat or reinforcement, sparse food and supplies, permitted no plausible circumstance in which the Japanese could have won the battle. US Marines (Left to Right), PFC. J. L. Hudson Jr. Pvt. K.L. Lofter, PFC. Paul V.Parces, (top of blockhouse), Pvt. Fred Sizemore, PFC. Henrey Noviech and Pvt. Richard N. Pearson pose with a captured Japanese flag on top of an enemy pillbox.