Iwo Jima 1945 Read online

  CONTENTS

  Introduction

  Timelines

  Historical Background

  Strategic Planning

  Operational Planning

  Planning Operation Detachment

  The Armies

  Commanders

  US Marines

  The Japanese

  The Days Before the Assault

  The Invasion Plans

  Gathering Intelligence

  Logistics and Administration

  Training and Rehearsals

  Sailing to Iwo Jima

  The Preliminary Bombardment

  Securing the Beachhead (D-Day to D+7)

  D-Day, 19 February 1945

  Cutting off Hot Rocks (D+1 to D+4)

  4th Division Advances toward Airfield 1

  The Battle for Hot Rocks (D+1 to D+4)

  The Battles for Airfield 1 and the Quarry (D+1 to D+2)

  The Advance towards Airfield 2 and Minami (D+3 and D+4)

  Clearing Airfield 2 and the Advance to Charlie-Dog Ridge (D+5 to D+7)

  Securing the Island (D+8 to D+19)

  5th Division’s Advance to Hill 362A and Nishi Ridge (D+8 to D+14)

  3rd Division’s Advance to Motoyama and Airfield 3 (D+8 and D+14)

  4th Division in the Meat Grinder (D+8 and D+14)

  5th Division’s Advance to Kitano Ravine (D+15 to D+19)

  3rd Division’s Advance to the East Coast (D+15 to D+19)

  4th Division Takes Minami and Higashi (D+15 to D+19)

  The Final Phase (D+20 to D+35)

  RCT 21 Advances to Kitano Point (D+25)

  4th Division Clears Tachiiwa Point (D+20 to D+25)

  To Kitano Point (D+20 to D+25)

  The Battle for Kitano Gorge (D+20 to D+35)

  The Final Days

  The Legacy

  Leaving Iwo Jima Behind

  The Cost

  The Battle for Okinawa

  The Atomic Bomb

  Orders of Battle

  Further Reading

  INTRODUCTION

  On 7 December 1941, Japanese planes attacked Pearl Harbor in the Hawaiian Islands and bases in the Philippines, bringing the United States of America into the Second World War. The first naval battle took place in May 1942, when Allied ships prevented a Japanese fleet taking control of the seas north of Australia. In the four-day Battle of the Coral Sea the Allied forces suffered heavy losses, but they achieved their objective of thwarting the Japanese invasion plans.

  Admiral Isoroku Yamamoto wanted to lure the US Navy into battle to get the upper hand in the Pacific. It was clear that a new style of naval warfare was developing, one in which the aircraft carrier played the leading role instead of the battleship. Technological advances in aerial warfare meant that planes could track down and destroy enemy ships long before the fleets saw each other.

  Allied code breakers had broken the Japanese naval code by late May 1942 and when they discovered that Yamamoto intended to capture Midway Island, halfway between Japan and Hawaii, US carriers sailed towards it looking to outmanoeuvre their adversaries. Contact was made on 4 June and in the battle that followed four Japanese carriers were destroyed or damaged, resulting in a decisive US Navy victory. Midway would later be seen as a turning point in the Pacific War.

  While the Japanese had been stopped in the Eastern Pacific, they were still on the offensive in the Western Pacific, advancing in the Solomon Islands and in New Guinea. But they had been stopped by September 1942 and the Allies counterattacked later in the year. General William Slim’s British and Indian XIVth Army was also holding its own in Burma.

  US Marines had landed on Guadalcanal in the Solomon Islands in August 1942 but it took a six-month-long deadly battle of attrition to clear it. The stubborn Japanese defence was a taste of what was to come in the Allied island hopping campaign, as they moved slowly across the Pacific towards the Japanese homeland. Islands had to be invaded, secured and then turned into air and naval bases ready for the next stage of the campaign. While many islands were captured, others – such as Truk, Rabaul and Formosa – were bypassed and bombed into submission.

  The invasion of the tiny Tarawa Atoll in the Gilbert Islands in November 1943 was a bloody experience for the Marines but they learnt many lessons about amphibious landings that were applied at Iwo Jima fifteen months later. At the same time, President Franklin D. Roosevelt, Prime Minister Winston Churchill and Generalissimo Chiang Kai-shek met in Cairo to agree a strategy to defeat Japan. While America was gearing up its industrial capacity for war, equipping not only its own armies but that of China, the Japanese Armed Forces were suffering because of the country’s lack of industry and resources.

  While the United States Navy and Marines were advancing slowly across the Pacific, the Imperial Japanese Army struck back in the India-Burma-China Theatre. While Operation U-Go, an offensive into India in March, was stopped at Kohima and Imphal, Operation Ichi-Go, a couple of months later, struck deep into China to attack Allied airfields.

  The invasion of Saipan in the Marianas Islands on 15 June 1944 was the next step in the Eastern Pacific and over 125,000 Army troops and Marines would eventually be involved in the battle for the island. Virtually every available Japanese ship was ordered to the area but the air attacks on Fifth Fleet, starting on 19 June, were a complete disaster. The Japanese Navy lost three aircraft carriers and 450 planes in the two-day battle while the US Navy only lost 130 planes; most of them crashed while trying to land on their carriers. The Japanese carrier fleet never recovered from what became known as the Great Marianas Turkey Shoot.

  General Douglas MacArthur then began his invasion of the Philippines Islands in the southwest Pacific; over 600 Japanese ground-based planes were destroyed trying to stop it. The Japanese Navy tried next and the four-day Battle of Leyte Gulf in October 1944 became arguably the largest naval battle in history; it was also the first time that Japanese pilots carried out kamikaze attacks, crashing their planes into carriers and battleships in a desperate attempt to sink them. Instead three Japanese carriers were sunk and a fourth was disabled on 24 October; another was sunk the following day, ending the Japanese Navy’s ability to carry out attacks. It left Sixth Army free to expand its beachhead on Leyte and by the end of December the island was secure.

  The rest of the Philippines operations followed, with an amphibious assault of Mindoro in December and Luzon in January; by 3 February US troops were in the capital, Manila. Luzon would become the largest campaign of the Pacific War while the invasion of Mindanao in April would complete the conquest of the Philippines.

  The Allied offensives in Burma continued throughout 1944 and American troops linked up with Chinese troops in the north in January. To the south, Japanese troops had withdrawn to a defensive line along the Irrawaddy river but the British XIVth Army crossed it on a broad front in February.

  By the time V Amphibious Corps landed on the shores of Iwo Jima on 19 February 1945, Imperial Japan’s Armed Forces were falling back on all fronts. Only this time American troops were stepping onto Japanese soil and there was no doubt about it, General Tadamichi Kuribayashi and his troops would fight to the last man to stop the US Marines taking it.

  TIMELINES

  The Pacific War before Iwo Jima

  1944

  15 June US Marines invade Saipan in the Mariana Islands.

  15/16 June The first bombing raid against Japan since April 1942.

  19 June Climax of the ‘Marianas Turkey Shoot’ when US carrier-based fighters shoot down 220 Japanese planes; only 20 American planes are lost.

  8 July Japanese troops withdraw from Imphal.

  19–27 July US Marines invade Guam in the Marianas.

  24 July US Marines invade Tinian.

  8 Au
gust US troops complete the capture of the Mariana Islands.

  15 September US troops invade Morotai and the Paulaus.

  20 October US Sixth Army invades Leyte in the Philippines.

  23–26 October The Battle of Leyte Gulf results in a decisive US Navy victory.

  25 October First suicide air (Kamikaze) attacks made against US warships around Leyte.

  11 November Iwo Jima bombarded by the US Navy.

  15 December US troops invade Mindoro in the Philippines.

  17 December US Army Air Force establishes 509th Composite Group and it starts practising how to drop an atomic bomb.

  1945

  3 January General MacArthur is placed in command of all US ground forces and Admiral Nimitz in command of all naval forces ready to assault Iwo Jima, Okinawa and Japan.

  9 January US Sixth Army invades Lingayen Gulf on Luzon in the Philippines.

  3 February US Sixth Army enters Manila.

  16 February US troops recapture Bataan in the Philippines.

  19 February V Amphibious Corps invade Iwo Jima.

  The Battle for Iwo Jima

  1945

  19 February 4th and 5th Marine Divisions land on Iwo Jima’s southwest shore. Mount Suribachi is isolated and parts of Airfield 1 are captured; 30,000 Marines are ashore by nightfall.

  21 February 4th Division clear Airfield 1. Japanese make Kamikaze attacks against the fleet off the coast of Iwo Jima; carrier Bismark Sea sunk and carrier Saratoga damaged.

  23 February Marines reach the top of Mount Suribachi and raise the Stars and Stripes.

  24–28 February 5th Division advance along the north coast towards Hill 362-A.

  3rd Division cross Airfield 2 and take Hill Peter and Hill 199-0.

  4th Division encounter the Meat Grinder near Minami village.

  1–5 March 5th Division capture Hill 362-A and Nishi and advance towards Kita.

  3rd Division seize Airfield 3 and Hill 357.

  4th Division encounter the Meat Grinder near Minami village.

  4 March The first B29, Dinah Might, makes an emergency landing on the island.

  6–10 March 5th Division capture Kita and Hill 362-B and then close in on Kitano Gorge.

  3rd Division capture Hill 362-C and advance rapidly to the east coast.

  4th Division seize Higashi village but cannot take the Meat Grinder.

  11–16 March 5th Division close in on Kitano Gorge in the north of the island.

  3rd Division clear Cushman’s Pocket east of Motoyama village.

  4th Division clear organised resistance south of Higashi.

  17–24 March 5th Division clear the final pocket of resistance in Kitano Gorge.

  3rd Division search tunnels and caves across the island.

  26 March Operation Detachment declared complete after 35 days; General Schmidt and V Amphibious Corps leave the island.

  12 April The last Marine units leave Iwo Jima.

  The Pacific War after Iwo Jima

  1945

  3 March The fall of Manila in the Philippines.

  10 March US Eighth Army invades Mindanao in the Philippines.

  1 April US Tenth Army invades Okinawa.

  7 April P-51 Mustangs based on Iwo Jima escort B-29s over Japan for the first time.

  12 April President Roosevelt dies; he is succeeded by Harry S. Truman.

  8 May Victory in Europe Day.

  25 May US Joint Chiefs of Staff approve Operation Olympic, the invasion of Japan, scheduled for 1 November.

  9 June Japanese Premier Suzuki announces Japan will fight to the end.

  18 June Japanese resistance ends on Mindanao in the Philippines.

  22 June Japanese resistance ends on Okinawa.

  10 July 1000 bomber raids begin against Japan.

  14 July The first US Navy bombardment of the Japanese home islands.

  16 July First atomic bomb successfully tested in the United States.

  26 July Atomic bomb ‘Little Boy’ delivered to Tinian Island in the South Pacific.

  6 August First atomic bomb dropped on Hiroshima.

  8 August USSR declares war on Japan and then invades Manchuria.

  9 August Second atomic bomb is dropped on Nagasaki; Emperor Hirohito and Japanese Prime Minister Suzuki decide to seek an immediate peace.

  14 August Japanese accept unconditional surrender.

  29 August US troops land near Tokyo.

  2 September Formal Japanese surrender ceremony on board the USS Missouri in Tokyo Bay.

  8 September General MacArthur enters Tokyo.

  HISTORICAL BACKGROUND

  Strategic Planning

  As early as September 1943 the Joint War Planning Committee met in Washington to discuss plans for the campaign against the Japanese homeland. The Central Pacific Forces had first to neutralise the Caroline Islands so that new sea and air bases could be established; only then could attacks be launched against the Japanese Navy. The Army Air Force also wanted air bases on the Mariana Islands so their new long-range B-29 Superfortress bombers could start bombing mainland Japan.

  The Committee identified the capture of one of the Nanpo Islands, midway between the Marianas and Tokyo, as an objective for early 1945. The islands were a vital part of the Japanese outer defences and the largest island in the Volcano Island group, Iwo Jima, was singled out as a key objective. Long-range fighters could then use the island’s airfields to escort the bombers to Japan; returning damaged bombers could also land on the island.

  In March 1944 the invasion of the Marianas was scheduled for 15 June and it would be the first stage in the advance towards the Japanese homeland.

  At the end of June a paper entitled ‘Operations Against Japan Subsequent to Formosa’ proposed advancing from the Mariana Islands to the Nanpo Islands in April 1945. On 12 August the Joint War Planning Committee submitted an outline plan for the invasion of Iwo Jima to the Joint Staff Planners. It listed the following advantages of taking the island:

  1. It would take a strategic outpost from the Japanese.

  2. Fighter planes could provide air cover for the new bases on the Marianas.

  3. Fighter planes would also provide protection for bombers heading for Japan.

  4. Bombers could use the island for staging attacks on Japan.

  The US Armed Forces continued their operations across the Pacific throughout the summer of 1944. Saipan, Tinian and Guam were taken, clearing the Marianas by the end of August. While the Japanese Navy Air Service suffered heavily, the US Air Force went from strength to strength as new air bases were built. The continued successes convinced the US High Command that they could take any island in the Pacific if sufficient naval, amphibious and shore-based air forces were made available. It meant that an attack on Iwo Jima had become a case of when, not if.

  The Pacific War at the end of 1944 involved simultaneous attacks on the Philippine Islands and the Marianas Islands.

  Codename Operations Tentative Target Date

  Forager Capture of Saipan, Guam and Tinian 15 June 1944

  Stalemate Capture of Palau 8 September 1944

  Insurgent Occupation of Mindanao 15 November 1944

  Causeway Capture of Southern Formosa and Amoy 15 February 1945

  Induction Capture of Luzon 15 February 1945

  Joint Staff Planners presented the Joint Logistics Committee with its plans for the invasion of Iwo Jima by September, asking for three divisions to be ready for 15 April 1945. Admiral Chester W. Nimitz told Lieutenant General Holland M. Smith, Commanding General of the Fleet Marine Force, Pacific, to keep the 2nd and 3rd Marine Divisions ready in the Marianas as a reserve for the invasion of Formosa; they would then be used to attack Iwo Jima.

  However, the Navy, Army, and Army Air Force commanders were all reconsidering the need for the invasion of Formosa. Admiral Nimitz had originally wanted bases in Formosa ready to strike the Chinese coast but recent Japanese gains in the area made him change his mind. Meanwhile, both Lieutenant General Robert C. Ric
hardson Jr, Commanding General, Army Forces, Pacific Ocean Areas, and Lieutenant General Millard F. Harmon, Commanding General of the Army Air Forces, Pacific Ocean Areas, wanted to strike Iwo Jima instead of Formosa.

  Admiral Nimitz, Admiral Ernest J. King (Commander, US Navy and Navy member of the Joint Chiefs of Staff), Admiral Raymond A. Spruance (Commander, US Fifth Fleet) and Lieutenant General Simon B. Buckner (Tenth US Army Commander and Commander of the Formosa Landing Force) met late in September in San Francisco to make the decision. The meeting illustrated that there were insufficient troops for the Formosa and southeast China operations. The War Department was also refusing to increase troop numbers in the Pacific until the war in Europe was over. Instead, Admiral King explained that there were enough forces for a different strategy. Iwo Jima in the Nanpo Islands would be taken first in January 1945; fighter support could then be provided for the B-29s raiding Tokyo. The capture of Okinawa Island in the Nansei Islands (also called Ryukyu Islands) would provide a staging area for the invasion of the Japanese mainland.

  Admiral King returned to Washington and the Joint Chiefs of Staff approved the change in strategy. They issued a new directive to Admiral Nimitz in which he was told to prepare for the following operations:

  1. Provide fleet cover and support for the attack on Luzon; target date 20 December 1944.

  2. Occupy one or more of the Nanpo Islands; target date 20 January 1945.

  3. Occupy one or more of the Nansei Islands, target date 1 March 1945.

  On 9 October 1944 Admiral Nimitz told General Holland M. Smith (nicknamed ‘Howling Mad’), to prepare for an invasion of Iwo Jima.

  The Joint War Plans Committee issued a paper called ‘Operations for the Defeat of Japan’ on 18 October outlining the advantages of capturing Iwo Jima:

  1. It would establish sea and air blockades.

  2. It would allow B-29 bombers to carry out air attacks on the Japanese mainland.