On October 12, 1960, 17-year-old Otoya Yamaguchi stabbed Socialist leader Inejirō Asanuma in Tokyo’s Hibiya Public Hall with a wakizashi — his father’s short sword.
An assassination that, in official accounts, is still given little significance. It is said that Yamaguchi was merely a follower of a right-wing group and that the act had no notable influence on Japan’s politics.
Yet nothing could be further from the truth.
Otoya Yamaguchi may not only have saved Japan from socialism — he may have altered the course of the world.
This is his story
Born in 1943 in Tokyo, son of Justice Ministry official Shinpei Yamaguchi.
Otoya grew up in the narrow alleys of Kojimachi or Nagatachō — old Tokyo neighborhoods where Japanese tradition still lingered, yet the concrete of modern Japan was already overshadowing history and promising the future.
Tokyo had once been a city of countless paper-and-wood houses, grown over centuries.
But on the night of March 10, 1945, incendiary bombs wrapped the city in flames, turning it to ash in a single night. More than one hundred thousand lives were lost, millions were left homeless.
Otoya Yamaguchi spent his childhood in post-war Tokyo under Allied occupation.
His father, Shinpei Yamaguchi, was an official in the Ministry of Justice, located at that time in the government district of Kasumigaseki (霞が関) in Chiyoda, Tokyo.
The Yamaguchi family therefore lived in one of the nearby neighborhoods — Kojimachi (麹町) or Nagatachō (永田町) — areas traditionally inhabited by government officials, not far from the Hibiya Public Hall.
Many of the old government residences in those districts survived the firebombing, and so Otoya spent his youth between tradition and modernity.
The Dawn of a New Japan
With the end of Emperor Hirohito’s rule, democracy began to take root amid the turmoil of reconstruction.
Political Climate of the Postwar Era
After Japan’s surrender in 1945, a profound political transformation began.
The American occupation under General Douglas MacArthur dissolved the old military administration, introduced a new constitution, and established a parliamentary system modeled on the West.
While the cities still lay in ruins, parties, labor unions, and political movements of every kind emerged — from monarchist-nationalist to socialist-communist currents.
During this time of upheaval, Japanese society became politically vocal.
Labor unions demonstrated in the streets, students organized in universities, and fiery debates raged in parliament, often ending in physical brawls.
The young democracy was alive but unstable — its factions deeply divided.
The 1955 System
In 1955, the so-called “1955 System” took shape, defining Japan’s political landscape for decades:
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The Liberal Democratic Party (LDP), still governing Japan today, was formed from the merger of two conservative groups. It was pro-American, economy-oriented, and focused on stability.
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The Socialist Party of Japan (SPJ) became the main opposition, uniting unions, intellectuals, and students who sought a neutral or pro-Chinese course.
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Smaller parties, including the Japanese Communist Party (JCP), held little power but fueled constant tension through agitation.
A Nation in Protest
The political climate grew increasingly heated. Between 1958 and 1960, Japan witnessed massive street protests, especially against the new U.S.–Japan Security Treaty (ANPO).
This movement united leftists, students, and pacifists determined to end Japan’s dependence on the United States.
Amid this unrest grew Otoya Yamaguchi.
He watched politicians who had once sworn loyalty to the Emperor now preaching Western values and embracing American order.
Between 1959 and 1960, he was arrested several times — not for crimes, but for his presence at political rallies and clashes common on all sides in those turbulent years.
A Divided Japan
Violence in Tokyo’s political scene was not a fringe phenomenon.
Fifteen years after the war, Japan’s future direction was fiercely contested:
Should the nation align with the West or the East, with democratic capitalism or socialist central planning?
Amid it all stood the imperial loyalists, who remembered that the modern Empire had led Japan from poverty into modernity, improving life even for ordinary workers.
The imperial era was still seen by many as a golden age of Japan.
This atmosphere shaped Otoya — and soon paved the way for the act that would make him immortal.
Otoya’s Political Environment
In the charged atmosphere of the late 1950s, Otoya Yamaguchi searched for direction.
He initially found it within the Greater Japan Patriotic Party (Dai Nippon Aikokutō) — a small but outspoken nationalist movement led by the charismatic publicist Akao Bin.
Akao saw his party as a bulwark against communism.
He was not a militarist but a passionate orator who believed that Japan could preserve its dignity only by remaining firmly aligned with the Western alliance, honoring the monarchy, and fighting Marxism without compromise.
His speeches in front of government buildings and universities became rallying points for those who saw in rapidly Americanized postwar Japan a moral vacuum.
The seventeen-year-old Otoya joined this movement.
He wore the uniform of the party’s youth wing, distributed flyers, and took part in demonstrations.
But soon he began to see his leader’s words as too weak.
In Otoya’s eyes, Akao talked too much and acted too little.
Western sources today often describe the Dai Nippon Aikokutō as a right-wing extremist or ultranationalist group.
From a Japanese perspective, however, it was nothing of the sort.
It was a monarchist and patriotic movement that demanded respect for the Emperor, rejection of communism, and national self-assertion under American protection.
For many young members, the party was a vent — a place to debate and take action.
But Otoya saw more than others.
The rapid rise of Inejirō Asanuma, a gifted speaker with strong ties to communist networks, posed a direct threat to his homeland — and Otoya decided that he had to act.
The Opponent: Inejirō Asanuma
Inejirō Asanuma was the face of Japan’s political left.
Born in 1898 in Chiba, he began his political career in the 1920s as a member of the Socialist Masses Party, which during the war was initially loyal to the Emperor.
After 1945, Asanuma — like many politicians of his generation — transformed from imperialist to socialist.
He quickly rose through the ranks of the Japan Socialist Party (Nihon Shakai-tō) and became its chairman.
Asanuma was a charismatic orator — loud, passionate, and stirring.
He spoke of the “brother nation China,” of a shared struggle against imperialism, and of a socialist Japan free from American influence.
In 1959, he traveled to China at the invitation of Beijing, where he was personally received by Mao Zedong.
He saw a nation scarred by civil war and revolution, yet experienced the staged spectacle of the new People’s Republic — full of propaganda and promise.
Despite reports of famine, persecution, and mass death under Mao’s rule, Asanuma returned enthusiastic.
He publicly declared that Japan and China should walk a common path, promoting the idea that Japan must detach itself from the West and ally with Mao’s China.
Shortly thereafter, he proclaimed in a speech that the United States was the common enemy of Japan and China — a statement that struck the conservative camp like a declaration of war.
Even though Asanuma’s party was still far from achieving a majority, his rhetorical talent drew massive crowds.
For socialism always tends to radicalize itself.
Otoya Yamaguchi saw communism rising on the horizon as the greatest threat to Japan’s spirit.
He knew that under China’s doctrine of equality, his nation’s traditions and identity would be erased — and Asanuma embodied everything that, in his eyes, would lead Japan to ruin.
In the months before the assassination, Asanuma seemed dangerously close to becoming Japan’s most powerful politician.
And so, within Otoya, grew the resolve to do what he believed had to be done.
The Assassination at Hibiya Hall
On October 12, 1960, a major political event took place at Tokyo’s Hibiya Public Hall.
It was a televised debate between several parties, organized by the public broadcaster NHK.
On stage stood representatives of Japan’s main political factions — among them the charismatic leader of the Socialist Party, Inejirō Asanuma.
The audience consisted of students, officials, and journalists.
The atmosphere was tense. The year 1960 had been marked by weeks of mass protests against the U.S.–Japan Security Treaty (ANPO).
The socialist movement was loud, confident, and ready to turn the nation’s political tide.
As Asanuma spoke passionately, a slender young man in a black school uniform suddenly stepped onto the stage.
In his hand, he held a wakizashi — his father’s short sword.
It was Otoya Yamaguchi, seventeen years old.
Before security could react, Otoya rushed forward.
With a single, precise thrust, he struck Asanuma in the chest.
The socialist leader collapsed instantly.
The live broadcast captured the moment — the expression of a young man who, calm and composed, without hatred on his face, withdrew his sword.
Otoya offered no resistance as he was arrested.
He said nothing, showed no remorse, and appeared as though he had done what he believed was inevitable.
At the police station, he later stated only that he had “to uproot evil before it could take root.”
This sentence engraved itself into Japan’s national memory and gave rise to the now-famous patriotic phrase:
“Never let evil take root.”
Images of the attack spread around the world.
In Japan, they triggered shock, disbelief, and quiet admiration.
Many saw Otoya as a madman — others as a patriot who dared to do what no one else would.
Even in a country accustomed to loud politics and street clashes, a public political execution shook the nation to its core.
Death in the Cell and the Legacy
After his arrest, Otoya Yamaguchi was transferred to Tokyo’s juvenile detention center.
He refused most interrogations, remaining calm and polite toward the officers.
He reportedly stated several times that he had no personal enemies — only the wish to eradicate evil at its root.
On the wall, he left words written in toothpaste:
“Seven lives for my country. Long live the Emperor.”
He tied a noose from a bedsheet and went into the next world.
Three weeks after the assassination, on November 2, 1960, Otoya was found dead in his cell.
In the following years, his name became a symbol of a lost generation — young, idealistic, and disillusioned with politicians wavering between East and West.
His act divided the nation but left a lasting mark.
Socialism in Japan never recovered from that blow.
The Socialist Party steadily lost influence in the years that followed, while the Liberal Democratic Party consolidated its power.
Japan remained pro-Western and capitalist, becoming one of the strongest economies in the world.
Thus ended the life of a seventeen-year-old student who had wielded his father’s sword for the future of his country — and changed the course of history.
Retrospect and Historical Significance
More than sixty years have passed since the day Otoya Yamaguchi wrote history into the sands of time with his sword.
In retrospect, it can be said that a rapprochement between Japan and China would have been a catastrophe for the entire Western world.
At the time of the act, the United States was at war — both in Vietnam and on the Korean Peninsula.
Russia and China, loosely aligned, supplied weapons, and the threat of nuclear war loomed on the horizon.
Japan, as the Western ally in the Pacific off China’s coast, was a decisive geopolitical anchor.
It maintained the balance between democratic capitalism and communist expansion — a balance that helped shape the fate of the Cold War.
Later, during its economic rise and industrial modernization, Japan played a key role in strengthening free trade and the prosperity of the Western world.
A socialist or communist Japan in the 1960s would have created a political imbalance that might have driven the world into catastrophe — perhaps even a Third World War.
We cannot know whether any of this — or none of it — would have come to pass had Inejirō Asanuma lived.
We only know that a seventeen-year-old student foresaw this future for Japan — and believed he had to prevent it.
Otoya Yamaguchi left behind no manifesto, no program, no party.
Only a single sentence the world has never forgotten:
“Never let evil take root.”
