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The USS Arizona

What if Japan never attacked Pearl Harbor?

The USS Arizona after the Japanese attack on Pearl Harbor | Public Domain

‘Yesterday, December 7, 1941 a date which will live in infamy, the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan.’

President Franklin D. Roosevelt.

It was the straw that broke the camel’s back; the sleeping giant had been awoken. The Japanese attack on the U.S. naval base at Pearl Harbor in the Pacific triggered America's entry into the Second World War. Up until that point, Uncle Sam had been following a policy of isolationism, determined to stay neutral with regards to foreign wars.

In the end, it took 353 Imperial Japanese aircraft just one morning to convince U.S. Congress to vote on a declaration of war, something Winston Churchill had been trying to get them to do for over two years.

Whilst Japan had hoped the surprise attack would demoralise American morale, the opposite was the case. Described by historians as ‘strategic imbecility’, the Japanese assault galvanised American support for the war. U.S. entry into the biggest global conflict the world had ever known was a pivotal moment in history and one that has since shaped the course of our world ever since.

But what if Japan had never attacked Pearl Harbor on that fateful day in December 1941? How different might the world look today? Here are two possible scenarios…

Scenario 1 – Japan & America still clash

Before Pearl Harbor, there was widespread public opposition to joining the war. Memories of the Great War still lingered in American minds; the last thing the public wanted was to see more of its young men die on foreign soil for a war they didn’t believe was theirs to fight. Remove Pearl Harbor and perhaps you remove American involvement in WW2.

However, it could be argued that even without that catalytic moment, Japan and America were already on an unavoidable collision course. For decades before the war, Japanese imperial ambitions saw the nation expand its influence politically and militarily to gain access to vital raw materials. This had led the country into a direct conflict with China.

In response, the U.S. placed sanctions on the Japanese. Oil embargoes, a resource the Japanese relied heavily on from the U.S., threatened to derail their expansionist efforts. Japanese alignment with Hitler’s Nazi Germany and Mussolini’s fascist Italy further raised tensions with the West. Throughout 1941, America and Japan engaged in negotiations but an agreement could not be met.

To become self-reliant the Japanese knew they needed the resources, especially oil, of Southeast Asia, most of which were held by weakly defended British and Dutch colonies. The Americans controlled the Philippines at the time, so any incursions into that part of the world would have brought on the wrath of the United States. So even if the Japanese hadn’t attacked Pearl Harbor, their imperial ambitions for Southeast Asia would eventually bring them into conflict with Uncle Sam.

FDR had already persuaded Congress to pass the Lend-Lease Act in March 1941 to ensure military aid was being provided to those fighting the Axis Powers. He’d also sent U.S. navy vessels to protect supply convoys shipped across the Atlantic to the British.

America was gearing for war; the attack on Pearl Harbor just gave the sitting U.S. president the excuse he needed to convince his country to finally get involved. Had it not come on 7 December 1941, it probably wouldn’t have been long before Japanese aggression in Southeast Asia led the two into direct conflict.

Scenario 2 – American isolationism continues, Japan consolidates

Whilst it’s true that FDR had been trying to get his country involved in the global conflict, he knew he could only go so far as public opinion before Pearl Harbor was incredibly anti-war. Isolationism was the policy of the time and opponents to the war held political sway. Even when most of Europe became occupied by Nazi Germany, America still wished to stay out of the fight.

Although FDR had been sending supplies to the Allies, he’d stopped far short of declaring actual war on any of the Axis Powers. Even when 100 American lives were lost aboard the USS Reuben James when it was sunk by a German U-boat near Iceland in October 1941, the U.S. still refused to join the war.

It’s not a far stretch to believe that the policy of neutrality was so strong in America that had Japan attacked British and Dutch territories in Southeast Asia and ignored Pearl Harbor and American controlled Philippines, the President would have had a hard time rallying support to retaliate. Would the U.S. have entered the war and risked American lives for British and Dutch colonial acquisitions? It would have been an incredibly hard sell for FDR to convince Congress, let alone the American people.

They might have sent naval vessels to the area but support for the war back home would have been a far cry from what it was after Pearl Harbor, which ignited a burning desire for revenge.

Without American intervention, D-day does not occur

By the time any U.S. naval forces would have reached the besieged territories, the Japanese could have fortified them sufficiently enough to prevent a full-on U.S. assault. If that were the case, the Japanese would then have been allowed to consolidate their territorial gains in the area, exploit the resources they now had under their control and continue their imperialistic ventures into China and further afield.

With regards to the war in Europe, the might and infinite resources of the Red Army would still see Hitler’s forces pushed back to Berlin, albeit a little later than in our timeline since Germany is not fighting on two fronts. Without American intervention, D-day does not occur like it did in our timeline. If the British and Canadians were able to muster an assault on mainland Europe it would most likely have come via the Italian peninsula or the Balkans, routes more favoured by Churchill. It was the Americans who pushed for Normandy.

Even if the reduced Allied forces managed to claim some territories back from the retreating Germans, the majority of Europe would turn red under Soviet control. There would be no East and West Germany, just Soviet-occupied Germany. The map of Europe would look vastly different than it does today. Perhaps American isolationism would then come to an end with the country conceding that the policy only benefitted the rise of Communism.

Without the war with Japan, no atomic bombs would have been developed and dropped on Hiroshima and Nagasaki. No nuclear arms race would have been set in motion; does the nuclear age (one that we very much live in today) even come into existence?

The ramifications that arise from this scenario certainly propose the theory that a world without Pearl Harbor is a world vastly different to our one now.