Few events have shaped the world in such violent and multitudinous ways as the events of World War II. Probably the most profound event was the use of atomic weapons on the cities of Hiroshima and Nagasaki. This decision was not made lightly and many factors led up to that ultimate outcome, one of those key factors was the Battle of Okinawa. During the Battle of Okinawa the Japanese fought so tenaciously down to almost the last man that it sealed their fate and convinced the President of the United States to use atomic weapons to end the war.
The road leading to the invasion of Okinawa, also known as Operation Iceberg (Rottman), began almost a decade earlier. In 1937 Japan, which already had troops stationed in Manchuria, invaded China in an attempt to control the entire eastern coast and seize vast amounts of resources and land. As Japan continued its march south, it also seized control of French Indochina and the islands of the Dutch East Indies. In an attempt to stop Japan the President of the United States, Franklin D. Roosevelt, ordered an oil embargo and froze all Japanese assets in the U.
S. This action was the prime contributor to the December 7th attack on the American fleet stationed at Pearl Harbor, Hawaii, which entered the U. S. into World War II (Esposito). In order to stop the Japanese advance through the Pacific the U. S. adopted an “island hopping” campaign that called for invasions of key islands throughout the Pacific Ocean that would cut off the Japanese supply lines and eventually take the war to the Japanese homeland. In April of 1945, it was determined that Okinawa would be the next island to be invaded.
The actual planning for Operation Iceberg began almost one year prior in May 1944. There were many considerations that had to be weighed before the decision was made on invading Okinawa. The decision for invasion was between Okinawa and the Formosa, an island 100 miles off the coast of China. Both options had their share of pro and cons, but Formosa was ultimately deemed too risky due to its’ large size and ability to be easily reinforced and it was agreed that Okinawa would be the next objective (Rottman).
Okinawa was a strategic island in the fact that its three main airfields were being used by Japanese fighters to harass Allied bombing missions heading toward mainland Japan. If the island could be secured then not only would air superiority be complete but that the U. S. could then use those same airfields to strike Japan as Okinawa is located only 320 nm from Japan’s southernmost island of Kyushu. Perhaps more importantly though is the fact that Okinawa would be used as an ideal staging ground for Operation Olympic, the planned invasion of mainland Japan.
Olympic had been scheduled for November of 1945 and would have required the use of 14 combat divisions and the largest naval armada in world history (Hallas). However, due to the actions on Okinawa, Operation Olympic was never launched. The Allied forces involved in Iceberg totaled 182,000 combatants divided into five divisions of the U. S. Tenth Army. The U. S. Army divisions involved were the 7th, 27th, 77th, 81st, and 96th , and two Marine divisions, the 1st and 6th, fought on the island while the 2nd Marine Division remained as an amphibious reserve and was never brought ashore.
The invasion was also supported by almost 1,500 U. S. and British ships. The Japanese forces on Okinawa totaled over 130,000 men divided into about 2 ? divisions. The primary combat units were the 62nd and 24th Divisions as well as the 44th Independent Mixed Brigade, all three units comprised the Japanese 32nd Army (Rottman). There are two key roles in any armed conflict, that of the combatant and that of the commander. For the Allies the overall commander was Admiral Raymond Spruance, he was in charge of Task Force 50 also known as TF 50, which was a robust mixture of massive Navy, Marine and Army forces.
Under TF 50 was Vice Admiral Richmond Turner who was in charge of all Allied ships within the Task Force, his sister commander was Lieutenant General Simon Buckner Jr, who commanded all land forces involved in the invasion and was also the highest ranking American killed in the battle. The Tenth U. S. Army was commanded by Lieutenant General John Hodge and his sister commander of the Marines from the III Amphibious Corps was Lieutenant General Roy Geiger who actually took over for Lieutenant General Buckner after his death on 18 June, 1945 and became the only Marine officer to ever command a field army (Rottman).
The Japanese counterparts to the Allied commanders included Lieutenant General Mitsuru Ushijima. He was the commander of the Japanese 32nd Army and was considered a mentor by his subordinates and was described as “coolly appreciative of reality” (Yahara). Ushijima selected Major General Isamu Cho as his chief-of-staff. Cho had a very different type of personality than Ushijima and was known for his strong emotions, enthusiasm, and boldness. Both Ushijima and Cho committed ritual suicide, hara-kiri, on June 23, 1945 after the bulk of the 32nd Army had been decimated by U.
S. forces. While of comparatively junior rank, an equally important, and unique, member of the 32nd Army staff was Colonel Hiromichi Yahara. Yahara was the senior operations and planning officer and was the highest ranking officer to survive the battle, and he advocated a war of attrition, which called for a carefully planned defensive strategy rather than an all-out attack (Tzeng). The invasion began on April 1, 1945, this was both Easter Sunday and April Fool’s Day.
It was known as L-day and nicknamed Love Day by the troops coming ashore. Even with over 100,000 troops at his disposal, Ushijima did not defend the beaches beyond some harassing indirect fire from artillery. This was done, for the most part, due to a change in the Japanese tactics and to conserve his resources. In previous island campaigns the standard Japanese tactic was to try and stop the landing at the water’s edge, this proved to be futile and a waste of men when defending against relentless allied bombardment.
Ushijima, and his superiors in Japan, knew that the Allies had superior firepower and personnel and that the entire war as well as the battle for Okinawa was in peril, so a new scheme of battle needed to be developed. It was believed that the Americans could not stomach losing large numbers of troops, so the plan was to make the Americans pay dearly for each yard they move forward. The expected result was thought to be that America would be open to negotiations and that Japan could set conditions for the war to end.
To help emphasize this concept Ushijima’s staff delivered a message to all Japanese fighters “ One Plane for One Warship. One Boat for One Ship. One Man for Ten of the Enemy or One Tank (Hallas). ” This created a paradigm shift in Japanese warfare. In earlier battles the Japanese, following the bushido code, would lead massive banzai charges against their enemy and sacrifice their lives in an attempt to overrun the opposition’s lines. This usually resulted in a total loss of Japanese lives and rarely captured did they capture their objective with this tactic.
In Okinawa, however, this was discouraged and men were instead instructed to fight to the last man and not to launch the infamous banzai charge. The only exceptions to this rule were to be one man suicide satchel charges on American tanks and the kamikaze attacks carried out by the Japanese Air Force on the Allied fleet in the surrounding waters. This new static defensive tactic called for massive cave and tunnel construction throughout most of southern Okinawa and used the natural landscape of ravines, cliffs and tunnels and was referred to as “Prairie dog warfare” by Buckner.
The most prominent example of this was the clash on Japanese main defensive line called the Shuri Line. This was a defensive network of caves and natural barriers that were tied in to Shuri Castle, the ancient capital of Okinawa and the 32nd Army Headquarters. The Shuri line was the 32nd Army’s main line of defense and stretched across the width of the southern portion of Okinawa, approximately 5 miles in width. On the western side of the Shuri Line, where the fighting was most fierce, was a collection of small hills that were nicknamed Sugar Loaf, Horseshoe and Halfmoon by the Americans.
The assault on these three hills caused large amount of casualties in a short span of time and were considered the most costly to the Allies at a total of over 3,000 killed in action in a six day period (Lacey). In a last ditch effort to push the Allies back Ushijima, at the protest of Yahara, launched a counteroffensive which resulted in 7,000 casualties for the Japanese in one day. This action further weakened the already strained Japanese defense and on May 19,1945 the Shuri Line was broken and the main defense was lost.
The remaining Japanese forces retrograded and fighting in small pockets of resistance still waged for over a month, and the island wasn’t finally declared secured until July 2, 1945. Fighting was not only limited to the southern portion of the island alone and while the northern portion had only a notional resistance the island of Ie Shima, located 5 miles off the central west coast, proved to be a very difficult objective to take and produced almost 1,500 U. S. casualties. It was at Ie Shima that the famous war correspondent, Ernie Pyle, was killed while reporting on the battle (Rottman).
In stark difference to the land tactics of limited suicide charges, the tactics in the waters surrounding Okinawa was a much different story. The Japanese had used kamikaze attacks in great numbers months earlier in the Battle of Leyte Gulf, now in Okinawa they would be used on an even greater scale. In an attempt to increase the radar range of the Allied fleet, destroyers were sent on radar picket duty and would form a large circle around the aircraft carriers and provide cover. It was these destroyers that took the brunt of the kamikaze aircraft and suicide motorboat attacks.
Over 1,500 Japanese aircraft were used in seven major attacks and multiple smaller attacks on American shipping. This resulted in 368 Allied ships damaged and 28 sunk with the human toll at 4,900 killed and 4,800 wounded (Reilly). The U. S. Navy sustained greater casualties in this operation than in any other battle of the war. On April 6, 1945 the Japanese sent the largest battleship ever built, Yamato, on a suicide mission to beach itself on the southern shores of Okinawa and use its massive guns on the Allies.
This was called Operation Ten-Go, or Heaven One, by the Japanese. However, the Yamato and most of her 9 escorts were spotted by American submarines and were sunk by U. S. Navy aircraft without ever coming close to their objective (Reilly). On July 2, 1945 after 82 days of the most vicious fighting of World War II the battle was declared officially over. The final costs of the battle were staggering to both sides, the Allies had over 12,500 soldiers, sailors and Marines killed or missing with over 65,000 wounded. The costs in materials were 36 ships sunk and 763 aircraft lost.
The Japanese had over 120,000 soldiers and sailors killed with only 7,400 wounded and taken prisoner, they had also lost 16 ships and over 4,000 aircraft (Rottman). Not to be forgotten is the civilian toll, the native Okinawans had lost over 100,000 people, many had been forced into military service or forced to commit mass suicide by the Japanese military when it appeared that the Allies were closing in (Lacey). Ninety percent of the buildings on the island were completely destroyed, and the lush tropical landscape was turned into “a vast field of mud, lead, decay and maggots (Tzeng)”.
However, the military value of Okinawa had exceeded all hope, it provided a fleet anchorage, troop staging areas, and airfields in close proximity to Japan. While the American military began preparations for Operation Olympic the President of the United States, Harry S. Truman, pondered a monumental decision. There were two options for victory: one was Operation Olympic which had an estimated cost of 109,000 allied dead/missing and 347,000 wounded, the other was the use of the new super weapons later known as Fatman and Little Boy.
After the carnage of Okinawa and in order to justify the use of atomic weapons in lieu of the land invasion President Truman stated “I do not want another Okinawa from one end of Japan to another (Tzeng)” Okinawa, with such high stakes, was only a fraction of the size of mainland Japan. The nation would savagely resist an invasion despite the depletion of her resources after her defeat at Okinawa. If the United States launched the invasion, the estimated million casualties, from both sides, and drainage of resources incurred would be unimaginable.
After much deliberation the decision was made by the president to use the new super weapons and force Japan to surrender quickly instead of dragging out a protracted war for even longer. On August 6th and 9th of 1945 the first and only atomic weapons used on civilian populations were dropped and 6 days later on August 15th 1945, Japan surrendered unconditionally and the war was over. It is truly ironic how the actions of the Japanese soldiers on Okinawa directly impacted their homeland in ways they couldn’t have imagined.
They defended Okinawa so strongly in an attempt to get America to end the war and negotiate peace. They were trying to save their countrymen, but by doing so they had also shown their resolve to never give up, never give in and to fight to the last man. They had given a glimpse of what could be expected if an attack of the homeland was launched. Their plan had, in turn, helped make a decision that had such a profound impact that it has never been made since.