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A photograph of The Atomic Bombing of Nagasaki, Japan on the 9th August 1945

Why Did Japan Really Surrender in WW2?

Image Credit: agilard / | Above: A photograph of The Atomic Bombing of Nagasaki, Japan on the 9th August 1945

“The Hiroshima bomb... It inflicted a serious body blow, but it was hardly a knock-out punch.”

Tsuyoshi Hasegawa

Could it really be possible that, all these decades later, after so many countless books, films, textbooks and TV documentaries, we’ve got the final days of World War Two all wrong? That the truth about the fall of Japan has been obscured by the smoke and fire and fallout of the nuclear attacks on Hiroshima and Nagasaki?

Some historians certainly think so. And it is their contention that the consensus on the end of World War Two completely ignores what really happened in 1945.


Let’s recap the conventionally accepted account of how the bloodiest conflict in the history of the world finally came to an end. In May 1945, the battle against the Nazis was done. Hitler was dead, his genocidal regime had been smashed, and there had been cheering in the streets of the Allied nations. But the celebrations were premature, because the war itself was very definitely not over.

Japan still stood firm, seemingly determined to fight to the bitter and bloody end. The question was, how to finally crush their seemingly unbending resolve? The battle in the Pacific had already distinguished itself by its horror and brutality, and the prospect of a full-scale ground invasion of Japan – a new D-Day – was nerve-jangling for millions of Allied soldiers.

But there was one possible way to avoid the mass casualties of a ground assault, and that was to unleash the awesome, unprecedented power of a new weapon: the nuclear bomb, which had been developed in secret by the United States.

Fair warning was issued to the Japanese in the form of the “Potsdam Declaration” of July 1945, which demanded the “unconditional surrender of all Japanese armed forces”. As the Declaration bluntly put it, “the alternative for Japan is prompt and utter destruction”.

The promise was carried out. On 6 August, a mushroom cloud rose above Hiroshima, heralding the dawn of a new, apocalyptic age. The city was utterly obliterated, as was Nagasaki in a second nuclear attack just days later. Cowed by such a show of force, and facing their own complete demise, the Japanese finally surrendered.

This is the standard take on the fall of Japan. As US Secretary of War Harry Stimson put it, the nuclear attacks were “our least abhorrent choice” and “ended the ghastly spectre of a clash of great land armies.”

But what if Stimson was wrong? What if everything you’ve just read misses the point completely?


“The Hiroshima bomb did not make the Japanese ruling elite feel as though their backs were to the wall. It inflicted a serious body blow, but it was hardly a knock-out punch.”

So says eminent historian Tsuyoshi Hasegawa. He and other dissenting voices believe that the real reason Japan surrendered was down to something far less titanic and earth-shattering than the nuclear bombs. One man, it seems, played a far more important part. And that man was Soviet dictator Joseph Stalin.

Many people today don’t realise that, while the Soviets had been allied with Britain and the US in the fight against Hitler, they were not actually at war with Japan at the time of the Potsdam Declaration. The Soviet Union and Japan had in fact signed a neutrality pact back in 1941, which served both their interests nicely. The Soviets could focus on taking on the Nazis without worrying about being attacked on the other side by Japan, while the Japanese were free to concentrate on their brutal battles with the US.

Things only changed on 9 August, the very day of the second atomic attack on Nagasaki, when the Soviets suddenly broke the pact, mounting a massive invasion of Japan’s territories that decimated Japanese troops.

Hiroshima had happened days before, but it was only now that the Japanese leaders fell into a panic. As historian Tsuyoshi Hasegawa puts it, “The Soviet entry into the war played a much greater role than the atomic bombs in inducing Japan to surrender because it dashed any hope that Japan could terminate the war through Moscow's mediation.”

That’s the key point: the Japanese weren’t fighting to win. They knew they’d have to give in eventually, but they wanted to surrender on the most favourable terms, in a way that would preserve their internal power structure, save their military leaders from war crimes trials, and avoid being a puppet state of the Allies. Until 9 August, they held out hope that the Soviets, as a neutral party, could help them negotiate the best deal with the US. During one meeting in June of that year, top Japanese military commander Torashirō Kawabe couldn’t have been clearer: “The absolute maintenance of peace in our relations with the Soviet Union is imperative for the continuation of the war.”

As historian Terry Charman tells us, “The Soviet attack changed all that. The leadership in Tokyo realized they had no hope now.” In fact, the situation was now completely reversed, with the Japanese fearing a Communist invasion which would overturn their rigid, imperial hierarchy and transform their nation forever. Immediate surrender was the only option.


Historian Ward Wilson, who vigorously disputes the significance of the Hiroshima and Nagasaki bombs, says “It’s very hard to make people give up their myths.” Indeed, in the case of the nuclear attacks, it borders on blasphemy.

For so many decades, the moral justification of Hiroshima and Nagasaki has been passionately debated. The standard argument in favour of US President Truman’s decision to drop the bombs has always been that, by unleashing such devastating force, the president avoided an even more devastating ground war that might have gone for many more months, taking untold numbers of Allied lives.

Not only that, but Hiroshima and Nagasaki have taken on an almost religious significance in the world’s consciousness – both because of the huge loss of civilian lives, and because of how these attacks signalled the beginning of a new and terrifying era in world history.

And yet, it can convincingly be argued that Hiroshima and Nagasaki were not hugely important in the context of Japan in 1945. What many people forget is that huge swathes of the country had already been utterly obliterated by the most extensive bombing raids the world had ever seen. These were conventional bombs, but no less effective at slaughtering civilians.

Tokyo, for example, had been completely incinerated, with around 100,000 people killed. US bomber crews could smell charred flesh as they flew over the firestorms. Dozens of other Japanese cities had been flattened under the never-ending barrage. Yet, despite this nationwide inferno, surrender wasn’t forthcoming. One politician, Kijūrō Shidehara, echoed the general sentiment when he suggested their “unity and resolve would grow stronger”, and that it was important to endure the attacks in order to negotiate the best outcome, further along the line.

So when President Truman, hinting at the nuclear attacks to come, said that the Japanese could “expect a rain of ruin from the air” if they didn’t surrender, it wasn’t really much of a threat. There had already been a rain of ruin, and it hadn’t changed the Japanese game-plan. When Hiroshima happened, Japan realised a new kind of weapon had been unleashed, but the devastation was not significantly different to what they had seen in countless cities already. It’s only from our vantage point today that the mushroom clouds eclipse everything else.


So if it really was the Soviet intervention that brought about the end of the war, why isn’t it more widely known? The fact is, the complicated period between the fall of Hitler and the fall of Japan haven’t received as much mass media attention as it deserves. While events like Dunkirk, the Battle of Britain, the D-Day landings, not to mention the controversial Allied attacks on Dresden, have all received plenty of media attention, the only thing most of us know about the endgame in Japan is that it saw the beginning of the nuclear age.

Even major events like annihilation of Tokyo in March 1945 are still not common knowledge, while the decisive Soviet invasion of 9 August is completely overshadowed by the Nagasaki attack that same day.

On top of that, when people think of the Soviet Union in World War Two, it’s not the Pacific theatre that comes to mind, but the savage skirmishes against Hitler’s forces, the massacres meted out by the SS in Russian towns and villages, the hellish confrontation in Stalingrad and the pivotal Nazi defeats that eventually turned the war against Hitler.