World War II: War in the Pacific

Learn about WWII's Pacific War: island hopping, code talkers, and the atomic bomb.

War in the Pacific By the end of March 1942, the Japanese had captured British Hong Kong and Singapore, the American islands of Guam and Wake, and the oil-rich Dutch East Indies. By this time, Japan had also invaded several larger possessions of the Allies, including the American-held Philippine Islands and the British colony of Burma.In the Philippines, Americans and Filipinos under General Douglas MacArthur resisted a fierce Japanese onslaught. Disease and malnutrition killed much of the defenders. Roosevelt ordered MacArthur to leave the islands in March, but upon his departure, the general promised, “I shall return.” Japan succeeded in conquering the Philippines two months later. Shortly thereafter, the Japanese rounded up 70,000 starving, exhausted American and Filipino prisoners on the largest island and marched them up the Bataan Peninsula near Manila to a prison camp. During the brutal 63-mile march, Japanese soldiers beat and bayoneted many of the prisoners—more than 7,000 died on the infamous Bataan Death March.The Americans led the Allied forces in the Pacific and did the bulk of the fighting there. When they went on the offensive, the Allies decided to liberate Japanese-held islands in the Pacific and then use them as stepping-stones toward Japan. In this way, each captured island served as a base for assaults on other islands as the Allies approached Japan.One of the keys to Allied success in the Pacific was the use of secret codes. The United States trained a special group of Navajo Indian “code talkers” for this task. Because Navajo is not a written language and is understood by very few people, it made an excellent code foundation. The Navajo code talkers played an important role in the Pacific campaign since they enabled the Allies to transmit vital information.A strategy known as leapfrogging or island hopping enabled the Americans to shift to the offensive with limited resources. In this method, the American forces would often leapfrog, or bypass, a heavily defended island to capture a nearby island that was not well defended. Then, the captured island was used as an airbase to bomb the well-defended, Japanese-held island and prevent ships from resupplying it. Cut off from reinforcements and supplies, the Japanese forces would be left to wither.The Allied push through the Pacific steadily shrank Japan’s defensive perimeter around its home islands, a security net that would all but disappear if the Allies could capture the key islands of Iwo Jima and Okinawa. Iwo Jima’s airfields would offer a place for B-29s to land in an emergency, and they would also serve as a base for fighter planes escorting bombers over Japan. Control of Okinawa, just 310 miles south of Japan, would provide a prime staging area for the U.S. invasion of Japan.On the small volcanic island of Iwo Jima, nearly all 22,000 Japanese troops followed their commander’s orders to fight to the death, and more than 6,800 American troops died to secure the island. The bloody combat of the Battle of Okinawa, much of it hand-to-hand, continued for two months. The battle claimed the lives of some 12,000 American soldiers and more than 100,000 Japanese.Earlier in the Pacific war, the Japanese introduced a new weapon called kamikaze pilots. In kamikaze attacks, hundreds of men flew their bomb-filled planes directly into Allied fleet vessels, sinking and damaging hundreds of ships. During these battles, the kamikazes failed to sink aircraft carriers, which were their main targets.The government established the Manhattan Project, a top-secret program to develop an atomic weapon. A team of scientists, many of whom had fled fascist European nations, conducted the project’s research and development. Their work was completed mostly at a lab in Los Alamos, New Mexico, and by the summer of 1945, their efforts had produced the first atomic bomb. On July 16, that test bomb was exploded on a remote airbase in the New Mexico desert.After the successful test of the atomic bomb, or A-bomb, President Truman had to decide whether to drop the bomb on Japan or launch a land invasion. an American naval blockade severed the supply of raw materials to Japan, and the combination of bombing and blockade left many Japanese starving. Even though many of Japan’s leaders realized that their country could not possibly win the war, they refused to accept Truman’s terms of unconditional surrender. In fact, they appeared determined to fight to the last man, woman, and child, in the spirit of the kamikaze.Truman did not compromise on his demand for unconditional surrender, informing Japan that its alternative was “prompt and utter destruction.” On August 6, 1945, a B-29 named Enola Gay dropped an atomic bomb on Hiroshima, Japan, a city of 300,000 people. Up to 80,000 people died within seconds of the explosion, the blast’s shock wave toppled nearly 60,000 structures, and hundreds of fires consumed the remainder of the city. Three days later, the United States dropped a second atomic bomb that obliterated the city of Nagasaki, killing some 40,000 people instantly. As many as 250,000 Japanese may have died from the two atomic bombs, either directly or as the result of burns, radiation poisoning, or cancer. Truman received Japan’s informal surrender on August 14, known as Victory over Japan Day, or V-J Day.Millions celebrated V-J Day, which marked the end of the Second World War, but they also mourned their severe losses. About 55 million died over the course of the war—30 million of them, civilians. The Soviet Union suffered the highest human loss; over 20 million of its people were killed. Some 400,000 Americans, nearly all in the military, gave their lives during the war. Most Americans believe strongly that these soldiers, sailors, airmen, and others died for a noble cause. Fill in the blanks using the word bank to help you. 1. Japan had many victories in the Pacific, including the Philippines, where defense forces were led by General Douglas MacArthur. 2. Disease and malnutrition killed many of the American defenders.3. One of the keys to Allied success in the Pacific was the use of secret codes.4. The special group that was trained as "code talkers were the Navajo Native Americans.5. The United States then adopted a strategy of island hopping to capture islands and move closer to Japan. 6. What TWO islands did the American soldiers need to capture to ensure victory over Japan? Iwo Jima and Okinawa.7. About 22,000 Japanese troops died on the island of Iwo Jima. About 12,000 Americans died during the Battle of Okinawa.8. American air forces then dropped bombs on major Japanese cities, and the Japanese responded with suicide pilots known as kamikazes. 9. The first atomic weapon was built and tested in New Mexico. 10. Japan's refusal to surrender and accept Truman's terms of unconditional surrender led the United States to use a new weapon: the atomic bomb. 11. An atomic bomb was dropped on Hiroshima on August 6, 1945. Up to 80,000 people died within seconds of the explosion.12. Three days later, another bomb was dropped on Nagasaki killing 40,000 people instantly.13. The immense destruction led to the surrender of the Japanese, and August 15, 1945, was proclaimed V-J Day.