AMSCO 7.13 World War II Military

Overview

AMSCO Topic 7.13, "World War II: Military," covers how the United States and its allies defeated the Axis powers on two fronts: Europe (with Britain and the Soviet Union against Germany) and the Pacific (where the U.S. did most of the fighting against Japan). The chapter runs from the turning points of 1942 through D-Day, the discovery of the Holocaust, island hopping, and the atomic bombings of Hiroshima and Nagasaki. It sits at the end of Period 7 (1890-1945), and the big skill here is explaining causes and effects: why the Allies won (cooperation, technology, and major campaigns) and what the war's end set in motion.

The chapter opens with J. Robert Oppenheimer's famous reaction to the first atomic test: "Now I am become Death, the destroyer of worlds." That quote signals where this story ends, so keep the moral questions about total war in mind as you read.

Fighting Germany: The European Theater

The German advance peaked in 1942 and then began rolling back, partly because the U.S. entered the war, but mainly because of the Soviet victory at Stalingrad in the winter of 1942. From there, the Allies squeezed Germany from the south, west, and east.

The Battle of the Atlantic and Strategic Bombing

In 1942, the British and Americans coordinated around two goals: stop German submarines in the Atlantic and start bombing German cities.

• The Battle of the Atlantic was the long naval fight to control shipping lanes. German U-boats sank over 500 Allied ships in 1942 alone.
• The Allies gradually contained the submarine threat with radar, sonar, and bombing of German naval bases.
• U.S. bombers flew daylight "strategic bombing" raids aimed at military targets, while Germany and Britain bombed each other's population centers. As the war went on, the line between military and civilian targets blurred, especially once the U.S. began firebombing Japanese cities.

From North Africa to Italy

The Allies first had to push German forces out of North Africa and the Mediterranean before attacking Europe itself.

• Operation Torch, the North Africa campaign, began in November 1942. Led by U.S. General Dwight Eisenhower and British General Bernard Montgomery, the Allies took North Africa from the Germans by May 1943.
• Next came Sicily, occupied in summer 1943 as a stepping stone to Italy. Mussolini fell from power that summer, but Hitler's forces rescued him and gave him nominal control of northern Italy.
• The Allies invaded the Italian peninsula in September 1943, but German troops resisted fiercely and held much of northern Italy until the final surrender in May 1945.

D-Day and the Push Toward Berlin

D-Day, June 6, 1944, was the largest invasion by sea in history. British, Canadian, and U.S. forces under Eisenhower's command secured beachheads on the Normandy coast of France.

• After the bloody but successful landing, the Allies moved fast. Paris was liberated by the end of August 1944.
• By September, Allied troops had crossed the German border for the final push toward Berlin.
• Germany launched a desperate counterattack in Belgium in December 1944, the Battle of the Bulge. It was a setback, but Americans reorganized and resumed the advance.

German Surrender and the Holocaust

Allied bombing since 1942 had worn down Germany's industrial capacity. With the Russian army closing in on Berlin, Hitler committed suicide on April 30, 1945, and the Nazi armies surrendered unconditionally on May 7.

As U.S. troops advanced through Germany, they came upon Nazi concentration camps and saw the full horror of the Holocaust: 6 million Jewish civilians and several million non-Jews systematically murdered by Nazi Germany. These revelations reinforced the American view of the war as a fight for the survival of freedom and democracy against fascist ideology.

Fighting Japan: The Pacific Theater

In Europe, Britain, the Soviet Union, and the U.S. shared the burden of defeating Germany, but in the Pacific the fight against Japan was largely a U.S. effort. After Pearl Harbor, Japan seized much of East and Southeast Asia. By early 1942, Japanese troops held Korea, eastern China, the Philippines, the Dutch East Indies (Indonesia), British Burma and Malaya, French Indochina (Vietnam, Cambodia, and Laos), and most Pacific islands west of Midway.

Midway: The Turning Point of 1942

The Battle of Midway (June 4-7, 1942) ended Japanese expansion. The Pacific war was dominated by naval forces fighting over a vast area, and the U.S. had a decisive edge: intercepting and decoding Japanese messages. That intelligence let U.S. forces destroy four Japanese carriers and 300 planes.

Island Hopping

After Midway, the U.S. needed to get within striking distance of Japan's home islands. The strategy was island hopping: seize strategic locations, bypass strongly held Japanese posts, and isolate them with naval and air power. Step by step, Allied forces moved toward Japan.

Leyte Gulf and Okinawa

Two battles stand out as the war closed in on Japan.

• Early in 1942, Japan had conquered the Philippines and driven out General Douglas MacArthur, commander of army units in the Southern Pacific, who vowed "I shall return." The Battle of Leyte Gulf (October 1944), the largest naval battle in history, virtually destroyed the Japanese navy and prepared the way for U.S. reoccupation of the Philippines. It also saw Japan's first use of kamikaze pilots, who made suicide attacks on U.S. ships.
• The Battle of Okinawa (April to June 1945) was colossal. Kamikazes inflicted major damage, and before taking this island near Japan, U.S. forces suffered 50,000 casualties and killed 100,000 Japanese. Those numbers shaped expectations for an invasion of Japan itself.

The Manhattan Project and the Atomic Bombs

After Okinawa, an invasion force stood ready to attack Japan, with extremely heavy casualties feared. But the U.S. had developed a new weapon. The top-secret Manhattan Project, run by General Leslie Groves, employed over 100,000 people and spent $2 billion to build a bomb powered by splitting the atom. J. Robert Oppenheimer, director of the Los Alamos Laboratory in New Mexico, successfully tested the first atomic bomb on July 16, 1945.

President Harry Truman (new to the job after FDR's death) and the Allies demanded Japan surrender unconditionally or face "utter destruction." When Japan's reply was unsatisfactory, Truman decided to use the weapon:

• August 6, 1945: atomic bomb dropped on Hiroshima.
• August 9, 1945: second bomb dropped on Nagasaki.
• About 250,000 Japanese died, either immediately or after prolonged suffering.

War and Morality

The atomic bombs sparked debates about the morality of targeting civilians, but the question wasn't new. Germany's submarine attacks on passenger ships raised it in World War I. In World War II, Germany and Britain bombed each other's cities on the theory it would force the other side to sue for peace. Postwar research found it didn't work; industrial output often went up because bombing urban centers freed workers from commercial jobs to staff hidden war plants.

Some argued that in modern industrialized societies, civilians were part of the war effort and therefore legitimate targets. The U.S. started with "strategic bombing" of only military targets but crossed the line with the firebombing of Japanese cities, which killed thousands of civilians. Nuclear weapons raised the stakes further: large-scale nuclear warfare could end most human life on Earth. This is a classic APUSH debate prompt, so know both the casualty-avoidance argument for the bombs and the civilian-targeting critique.

Japan Surrenders

Within a week of the Nagasaki bomb, Japan agreed to surrender, on the condition that the emperor could remain as a titular (powerless) head of state. General MacArthur received Japan's formal surrender on September 2, 1945, aboard the battleship USS Missouri in Tokyo's harbor. The diplomacy ending the war set the stage for efforts to build a more lasting peace, which carries you into the Cold War.

Key Terms to Know

Practice and Next Steps

Go deeper on this topic with the 7.13 World War II: Military course study guide, and review how it connects to earlier wartime content in AMSCO 7.5 World War I: Military and Diplomacy. For the bigger Period 7 picture, start with AMSCO 7.1 Contextualizing Period 7 or browse all APUSH AMSCO notes.

To test yourself, try guided multiple-choice practice on WWII content, write a response with FRQ practice and instant scoring, or look up terms like "island hopping" in the APUSH key terms glossary.