War Criminals and Aggressive War

A very few throughout the world, including these accused, decided to take the law into their own hands and to force their individual will upon mankind. They declared war upon civilization. . . .

-US Assistant Attorney General Joseph B. Keenan's opening at the International Military Tribunal for the Far East (June 4, 1946)


As Emperor Hirohito prepared for surrender in the summer of 1945, Japanese military leaders also saw that capitulation was imminent. Unlike other times in history when war was concluded, surrender to Allied forces this time included their arrest and prosecution for war crimes. The 1943 Moscow Declaration confirmed that the Allied forces sought to conduct trials against major war criminals, and Article 10 of the Potsdam Declaration stated that “stern justice shall be meted out to all war criminals, including those who have visited cruelties upon our prisoners.”1 Alongside these provisions, Japanese military leaders could not ignore the fate of leading Nazi officials awaiting trial at the International Military Tribunal (IMT) at Nuremberg.

Because of the efforts of the foreigners involved in the Nanjing Safety Zone to collect evidence, photograph, film, and send letters and other documentation to family and colleagues living outside China at the time, there was evidence of the atrocities committed in and around Nanjing. There were also women and men from Nanjing who survived the violence who were willing to step forward and tell their stories publicly.

Other cities and locations where war crimes and atrocities occurred did not have the same body of evidence. In a frantic attempt to avoid prosecution, Japanese military leaders took full advantage of the lag of time between their surrender (August 15, 1945) and Allied occupation (August 30, 1945.)2 A policy of systematically destroying and burning vast amounts of incriminating evidence, including transcripts of imperial conferences, records of the Supreme Council for the Direction of the War, all files on prisoners of war, orders and plans relating to the attack on the Philippines and Southeast Asia, and documents relating to the Manchurian and Chinese campaigns, were put in force.3  Many high- and low-ranking Japanese leaders also chose to end their lives and practice what Prime Minister Tojo termed as the “frontline code of honor” rather than be “judged before a conqueror’s  court.”4

Despite the tremendous loss of evidence and desperate acts by Japanese leaders, on January 19, 1946 General Douglas MacArthur, Supreme Commander of Allied Powers, established by Special Proclamation the International Military Tribunal for the Far East (IMTFE) and approved its Charter. MacArthur appointed a panel of 11 judges, 9 of whom were from nations who signed the terms of surrender5 The IMFTE used crimes against peace, war crimes, and conspiracy to commit these crimes in their indictments of Japanese war criminals and relegated them into a total of 55 separate counts to prosecute leading Japanese officials.

The counts were further divided into three levels, Class A, B, and C. Those most deemed responsible for aggressive war or crimes against peace were Class A war criminals. These counts included the following:



1:          As leaders, organizers, instigators, or accomplices in the formulation or execution of a common plan or conspiracy to wage wars of aggression, and war or wars in violation of international law.

27:        Waging unprovoked war against China.

29:        Waging aggressive war against the United States.

31:        Waging aggressive war against the British Commonwealth.

32:        Waging aggressive war against the Netherlands.

33:        Waging aggressive war against France (Indochina).

35, 36:   Waging aggressive war against the USSR.

54:        Ordered, authorized, and permitted inhumane treatment of Prisoners of War (POWs) and others.

55:        Deliberately and recklessly disregarded their duty to take adequate steps to prevent atrocities. 6 


Two of the Class A defendants, Prince Asaka Yasuhiko and General Matsui Iwane, were key military officers involved in the Nanjing Atrocities. Prince Asaka had spent his career in the Imperial Army, was the son-in-law of Emperor Meiji and uncle to Hirohito. He was never indicted, questioned as a witness, or brought to testify at the IMTFE because of his imperial affiliations. General Matsui was commander of both the Shanghai Expeditionary Forces beginning in August 1937 and the Central China Area Army (CCAA) by December 1937. Matsui directed the campaign to capture Nanjing and was deactivated from this position in March 1938. A third Class A defendant, Hirota Koki, was the foreign minister of the CCAA at the time of the occupation of Nanjing. Evidence was also gathered against Class B acts, war crimes, and Class C, crimes against humanity. These accused individuals would only be tried at the IMTFE if they were already being prosecuted for Class A acts.

Finally, the prosecutors at Tokyo faced the decision whether to prosecute Japan’s leader (Emperor Hirohito), who remained alive at the conclusion of the war. MacArthur was instructed by Washington and a Joint Chiefs order on September 12 to “take no action against the Emperor as a war criminal.” 7 This order was in direct conflict with Article 6 of the Nuremberg Charter, which the IMTFE Charter was loosely based upon. This article held heads of state responsible for committing acts of aggressive war, stating, “Leaders, organizers, instigators and accomplices participating in the formulation or execution of a common plan or conspiracy to commit any of the foregoing crimes are responsible for all acts performed by any persons in execution of such plan.”8 But General MacArthur and the personnel working for SCAP reasoned that the success of their occupation depended upon the stability of Japan. The prosecution and possible removal of the emperor could undermine this effort and jeopardize the American interests in the region.9 MacArthur even received direct instruction from Washington to “take no action against the Emperor as a war criminal.” 10

This rationale was not shared by all of the Allied forces with interests in Japan. For example, the Australians furnished a detailed memorandum advocating for the prosecution of the emperor. It stressed never “at any time was Hirohito forced by duress to give his written approval to any aggressive military action.” 11  In the end, the American forces’ dominant role politically and militarily in the region won out and the emperor was not indicted. This decision was supported by the Soviet delegation, on instruction from Stalin, calling for Hirohito’s indictment only if the Americans agreed to it. Similarly the three Asian countries participating in the tribunal, China, the Philippines, and India, would only pursue prosecuting the emperor if the Americans agreed to. Ultimately, 28 Japanese defendants were indicted but Emperor Hirohito was not included.


Less than one year after Japan’s surrender, former US assistant attorney general Joseph B. Keenan opened the IMTFE on June 4, 1946. The statement was given at Ichigaya Court in Tokyo, the former headquarters of the Imperial Army in Tokyo during the war:

Mr. President and members of the International Military Tribunal for the Far East: . . .

This may be one of the most important trials of history. It is important to the eleven nations here represented, constituting orderly governments of countries containing much more than one-half of the inhabitants of this earth. It is important to all other nations and to the unborn generations, because these proceedings could have a far reaching effect on the peace and security of the world. . . .

Our broad aim is the orderly administration of justice; our specific purpose is to contribute all we soundly can towards the end—the prevention of the scourge of aggressive war. . . .

Mr. President, this is no ordinary trial, for here we are waging a part of the determined battle of civilization to preserve the entire world from destruction. This threat comes not from the forces of nature, but from the deliberate planned efforts of individuals, as such and as members of groups. . . . A very few throughout the world, including these accused, decided to take the law into their own hands and to force their individual will upon mankind. They declared war upon civilization. They made the rules and defined the issues. They were determined to destroy democracy and its essential basis—freedom and respect of [sic] human personality; they were determined that the system of government of and by and for the people should be eradicated and what they called a “New Order” established instead. And to this end they joined hands with the Hitlerite group. . . . Together they planned, prepared, and initiated aggressive wars against the great democracies enumerated in the indictment. . . .

No one needs even the slight reminder to realize that wars in our time are quite different from those of old. Today, and far more important still, tomorrow and forever hereafter wars can be nothing other than total wars.12


While some have criticized the Tokyo trials for selective prosecution or as an example of victor’s justice, others see the trials as an important legal milestone in the prosecution of crimes against humanity.

This is a general view of the International Military Tribunal for the Far East meeting in Tokyo in April, 1947.


  1. Citations

    • 1 : The Moscow Conference, Joint Four-Nation Declaration, USA-UK-USSR-China, October 1943, published in A Decade of American Foreign Policy: Basic Documents, 1941-49, prepared at the request of the Senate Committee on Foreign Relations by the Staff of the Committee and the Department of State, (Washington, DC: Government Printing Office, 1950) and online; and Harry S. Truman, Winston Churchill, and Chiang Kai-shek, The Potsdam Declaration, US-UK-China, July 26, 1945, accessed May 28, 2014.
    • 2 : This is the date General Douglas MacArthur arrived in Tokyo but Allied personnel had officially arrived on August 28, 1945.
    • 3 : Arnold C. Brackman, The Other Nuremberg: The Untold Story of the Tokyo War Crimes Trial (New York: William Morrow, 1987), 40.
    • 4 : Ibid., 44. By the end of August 1945 roughly 1,000 officers and men of the Imperial forces died by suicide. Tojo himself unsuccessfully attempted to end his life as the US military police moved in to arrest him in on September 8, 1945. He was resuscitated by US Army medics and would later stand trial at the IMTFE.
    • 5 : These included Australia, Canada, the Republic of China, France, British India, the Netherlands, New Zealand, the Philippines, the United Kingdom, the United States, and the USSR.
    • 6 : “The Tribunal - An Overview”, The Tokyo War Crimes Tribunal: A Digital Exhibition website, accessed January 1, 2014.
    • 7 : David M. Crowe, War Crimes, Genocide, and Justice: A Global History (New York: Palgrave MacMillan, 2013), 198.
    • 8 : “Article 6.,” in “Nuremberg Trial Proceedings Vol. 1; Charter of the International Military Tribunal,” at the Avalon Project website, accessed January 1, 2014.
    • 9 : Herbert Bix, Hirohito and the Making of Modern Japan (New York: Harper Perennial, 2001), 587.
    • 10 : Dower, Embracing Defeat. The international Far Eastern Commission exempted the emperor as a war criminal by April 1946.
    • 11 : Ibid., 592.
    • 12 : “Item 52 – Opening Statement of the Prosecution,” The Tokyo War Crimes Tribunal: A Digital Exhibition website, accessed January 1, 2014.

Connection Questions

  1. Is there a difference between moral responsibility and legal accountability? Who do you believe should be held legally accountable for the atrocities committed in Nanjing? Who would you hold morally accountable? What criteria would you use to answer those questions?

  2. What is the purpose of a trial? Is a trial the only option for seeking justice for those who were wronged?

  3. The Tokyo Trials are often compared to the Nuremberg Tribunals. From this reading, what are important differences between the two trials? Why are these differences noteworthy?

  4. Who do you believe is more responsible for war crimes that are committed, the leaders or the soldiers? Who should ultimately decide? Do you agree or disagree with the decision by the Supreme Command for the Allied Powers to not prosecute Emperor Hirohito for war crimes? What evidence can you cite within the reading supporting your stance?

  5. Justice Robert L. Jackson opened the Nuremberg Trial with the following statement:

    May it please Your Honors:

    The privilege of opening the first trial in history for crimes against the peace of the world imposes a grave responsibility. The wrongs which we seek to condemn and punish have been so calculated, so malignant, and so devastating, that civilization cannot tolerate their being ignored, because it cannot survive their being repeated. That four great nations, flushed with victory and stung with injury stay the hand of vengeance and voluntarily submit their captive enemies to the judgment of the law is one of the most significant tributes that Power has ever paid to Reason.

    This Tribunal, while it is novel and experimental, is not the product of abstract speculations nor is it created to vindicate legalistic theories. This inquest represents the practical effort of four of the most mighty of nations, with the support of 17 more, to utilize international law to meet the greatest menace of our times-aggressive war. The common sense of mankind demands that law shall not stop with the punishment of petty crimes by little people. It must also reach men who possess themselves of great power and make deliberate and concerted use of it to set in motion evils which leave no home in the world untouched. It is a cause of that magnitude that the United Nations will lay before Your Honors.

    (For the full transcript of the speech go to

    Compare Justice Jackson’s opening statement at Nuremberg with the opening statement of Justice Keenan at the Tokyo Trial excerpted in the reading. According to their statements, what objectives do both trials share? What differences in the trials are reflected in the opening statements?

  6. There were many Japanese suspects who escaped indictment for war crimes at the Tokyo Trials. In fact 120 Class-A war criminals were arrested, detained and were released.1 However, one unique case was Ishii Shirō, the Japanese leader responsible for Unit 731 - the Japanese sponsored bacteriological warfare and human experimentation program designed against Chinese civilians, soldiers and other POWs. The “oversight” of any prosecution for those responsible for Unit 731 was later revealed as a negotiated agreement between SCAP and Japanese authorities. In exchange for immunity, Ishii agreed to hand over all data from his germ warfare work to the Americans rather than risking the information getting into the hands of the Soviets.2

    Should political priorities of nations ever override holding individuals accountable for war crimes?


  • 1 : Bob Tadashi Wakabayashi (professor, York Univeristy), private correspondence.
  • 2 : Over 120 A-class war crimes suspects were arrested and detained but released without trial. Ishii Shirō was not overlooked by the Americans but instead was lavishly rewarded for handing over information.

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