By: John Banks
All changed the course of the war. Some changed the course of the world.
Major World War II decisions often hit like earthquakes, their shockwaves rippling across the globe. Some had immediate consequences, while others unfolded over months and years, altering alliances, strategies and borders.
From a secret pact to battlefield orders, each choice set off aftershocks. Here are 10 World War II decisions that changed the course of the war—and the world.
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In the agreement signed by Nazi foreign minister Joachim von Ribbentrop and his Soviet counterpart Vyacheslav Molotov, the two powers pledged not to attack each other and secretly agreed to divide Eastern Europe into spheres of influence. The pact rattled the world. For British Prime Minister Neville Chamberlain, who had pinned his hopes on diplomacy with Adolf Hitler, war now seemed imminent. “God knows I have done all possible in our efforts for peace," he said in London after the news broke.
Aftershocks:
The Nazis invaded Poland on September 1, 1939, prompting Britain and France to declare war—in effect, launching World War II. The Soviets invaded from the East 16 days later, and the two aggressors divided Poland.
Secret provisions of the pact placed the Baltic states—including Latvia, Estonia and Lithuania—within the Soviet sphere of influence.
Soviet leader Joseph Stalin gained a buffer period to build up defenses, and Hitler gained confidence to attack in Western Europe.
During WWII, Hitler's decentralized and paranoid military command structure spells disaster on the battlefield.
In his 1925 book Mein Kampf, Hitler signaled his intention to invade the Soviet Union—the world’s largest country—for “Lebensraum” (living space) for Germans. In late 1940, his “Führer Directive 21” made good on that promise, setting in motion Operation Barbarossa, a flagrant violation of their nonaggression pact. “Waiting would have been a crime against the German people,” Hitler reportedly said, reflecting his hatred of Stalin and Bolshevism.
Aftershocks:
The invasion opened the largest and deadliest theater of the war: Some 24 million Soviets perished, along with millions of German soldiers.
Germany’s failure to defeat the Soviets quickly led to a prolonged war of attrition that strained its military and resources.
Later in the war, Soviet forces pushed westward into Germany in a vengeance campaign that included widespread rape, pillaging and destruction of cities. Their 1945 capture of Berlin shaped the postwar division of Europe.
How did things get so bad between the US and Japan in the lead up to WWII? It all comes down to power and resources.
The decision to attack the American Pacific fleet—and gain control of the Pacific—rested with the highest levels of the Japanese government, notably Prime Minister Hideki Tojo. Execution, however, fell to Admiral Isoroku Yamamoto and his fleet.
Aftershocks:
Calls arose for U.S. governmental investigations into the attack, which killed more than 2,400 Americans. “One of the sharpest jolts this country ever received,” The New York Daily News wrote.
U.S. public opinion shifted fully toward total war mobilization. “Assembly lines are now in operation. Others are being rushed to completion,” President Franklin Roosevelt said in a Fireside Chat two days after the Pearl Harbor attack.
Within months, Japan expanded its offensive across Southeast Asia and the Pacific, capturing Guam, Hong Kong, Singapore and more.
Only four days after Pearl Harbor, Hitler railed against the Americans and English, saying in a declaration of war that they and “international Jewry” forced the conflict on Axis powers Germany, Japan and Italy. In asking Congress to declare war on Germany, FDR said: “Never before has there been a greater challenge to life, liberty and civilization.”
Aftershocks:
The U.S. now found itself fully engaged in both the European and Pacific theaters of the war.
Coordination deepened among the U.S., Britain and Soviet Union.
Germany faced America’s industrial and manpower might, tipping the strategic balance.
In July 1942, the Nazi Army bombs the Soviet city of Stalingrad, launching one of the bloodiest battles in history.
After the Soviets had encircled the German Sixth Army and its allies at Stalingrad, Hitler forbade its commander, Friedrich Paulus, to retreat—an order that effectively condemned nearly 100,000 German soldiers to captivity and thousands to death. Paulus surrendered on January 31, 1943—an act Hitler called treason.
Aftershocks:
The defeat of the Sixth Army—“essentially wiped out,” according to historian David Glantz—shattered German morale and ended the myth of Nazi military invincibility.
Hitler’s refusal to retreat hardened, leading to catastrophic decisions, including his directive to delay a surprise attack on Kursk in early July 1943, which doomed his military’s final offensive campaign. From that point on, the Nazis were on the defense.
In early 1943, British and American leaders intensified their strategic bombing of Germany, combining attacks of numerous key cities with strikes on key industrial and military targets. The aim? Break Germany’s war machine—and its morale. Make the enemy “burn and bleed,” British prime minister Winston Churchill said.
Aftershocks:
Strategic bombing forced critical German war industries underground, wrecked transportation networks and crippled oil production.
Civilians suffered terribly; the combined British-American bombing of Dresden alone claimed up to 25,000 lives. The air campaign killed nearly 353,000 Germans overall, historian Richard Overy estimated.
The decision to proceed with D-Day, the largest amphibious naval operation in history, rested largely with President Franklin Roosevelt and Churchill. But the ultimate decision to land more than 150,000 Allied troops on the French coast—which forced Hitler to split his forces and divert them from the Soviet Union—fell to Supreme Allied Commander Dwight Eisenhower.
Aftershocks:
The Soviets greeted the long-awaited new front with “lively enthusiasm,” the United Press reported from Moscow.
The pressure accelerated Nazi losses in occupied Europe and hastened the collapse of German resistance.
With Germany on its knees, Allied “Big Three” leaders FDR, Stalin and Churchill had their most consequential summit, where they reiterated that the Nazis must surrender unconditionally—a condition they first announced at their 1943 Casablanca conference. They also revealed that Germany (and its capital Berlin) would be partitioned into occupation zones for the Americans, British, Soviets and, eventually, the French. In addition, the trio agreed to hold Nazi leaders accountable at an international trial for war crimes.
Aftershocks:
Germany and Poland lost territory to the Soviets, and their borders shifted westward, laying the groundwork for the Cold War.
As communist influence spread in Eastern Europe, Churchill warned in a speech in Missouri in 1946 that “an iron curtain has descended across the continent.”
The 1945-46 Nuremberg Trials of Nazi war criminals captured global attention.
As both U.S. and Soviet forces closed in on Berlin in the spring of 1945, the Supreme Allied Commander anticipated heavy U.S. casualties and a logistical quagmire if both armies descended on the city. He instead sent a message to Stalin to have his forces seize the German capital—a long-coveted prize for the Soviets. With the decision already made to divide Germany into separate occupation zones, “there was no possibility of the Western Allies capturing Berlin and staying there,” Eisenhower later told an interviewer. Churchill, having not been consulted, vehemently objected, worried about the Soviets winning undue credit for the Allied victory—and undue influence over the "main prize" going forward.
Aftershocks:
The Soviets gained full control of Berlin and the surrounding area for two months, tightening their grip over Eastern Europe. That summer, they ceded territory to the other Allies, honoring the decision to create four occupation zones of both Eastern and Western influence.
Thousands of German scientists, engineers and technicians—especially those with nuclear weapons expertise—were rounded up and recruited by both the Soviets and Americans.
Eisenhower’s decision indirectly led to the Soviets’ Berlin Blockade (1948-1949) and construction of the Berlin Wall (1961). The Soviets maintained control over East Berlin for nearly 50 years.
In August 1945, the United States dropped two atomic bombs over the Japanese cities of Hiroshima and Nagasaki. What happened to people on the fringes of the blasts?
President Harry Truman authorized the dropping of atomic bombs to hasten Japan’s surrender and avoid a full-scale invasion that would result in untold GI casualties. After the bombing of Hiroshima on August 6, he warned of a “rain of ruin from the air.” Three days later, the U.S. dropped a second bomb on Nagasaki, bringing the estimated combined death toll to 120,000 in the initial blasts.
Aftershocks:
In a radio broadcast to his subjects on August 15, Emperor Hirohito announced Japan’s surrender; formal surrender came September 2.
U.S. Secretary of War Henry Stimson called the bombs “our least abhorrent choice,” though the controversy over their use remains.
Allied military leaders knew that casualties could be staggeringly high. Historians are still calculating the toll.
Austria’s national squad had been known as the 'Wunderteam,' but when conscripted to play for Germany, they were less impressive.
Neutrality was often more complex than simply avoiding choosing sides.
A longtime journalist, Banks was a senior editor for ESPN.com and The Dallas Morning News. His writing has appeared in The New York Times, Civil War Times, Civil War Monitor, Civil War News, America's Civil War and Military Images, among other publications.
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