An opinion piece posted on 10.05.2016 08:46 by Timothy Bancroft-Hinchey on Pravda states that Peter Kuznick claimed:

The Japanese leaders did not know that at Yalta Stalin had agreed to come into the Pacific War three months after the end of the fighting in Europe. But Truman knew this and understood the significance. As early as April 11, 1945, the Joint Intelligence Staff of the Joint Chiefs of Staff was reporting that "If at any time the USSR should enter the war, all Japanese will realize that absolute defeat is inevitable."

While credible given the numbers and proximity of the USSR to Japan, is there a source for that quote other than Kuznick's book?

  • Just to clarify: Are you asking for confirmation of this particular quote, or are you asking for independent evidence that the Joint Chiefs of Staff were convinced that a declaration of war by the USSR would convince Japan of imminent defeat?
    – Schmuddi
    Commented May 20, 2023 at 11:40
  • "As early as April 11, 1945" is kinda late in the war... Anyhow a quick search for the quote shows that it appears in a number of other publications. Why are you skeptical? Commented May 20, 2023 at 14:07
  • 2
    @Fizz Pravda was the earliest dated source I could find, and I don't own the book, hence my question. Commented May 20, 2023 at 17:29
  • @Schmuddi Given that one soldier named Onoda who solo'd WW2 until almost 30 years later, I doubt the content holds true, so the source of the quote, please. Commented May 20, 2023 at 17:31

1 Answer 1


The quote appears in some other papers like this 1991 one by Alperovitz & Messer with reference to the primary sources, which however are almost certainly not online:

Aside from the fact that it would be a rare intelligence officer who would commit himself unequivocally on so important point as precisely when Japan would surrender, a common sequence of argumentation appears in a series of key documents. A typical statement: If "the U.S.S.R. should enter the war, all Japanese will realize that absolute defeat is inevitable." Thereafter, goes this argument, the war can probably be ended rather quickly if Japan can be made to understand that unconditional surrender does not imply annihilation or national suicide.

accompanied by a footnote/citation:

Taken from preliminary estimate of the Joint Intelligence Staff on April 11, 1945, NA, RG 165, Entry 421, ABC Decimal File 1942-48, Box 504, "ABC 387 Japan (15 Feb. 45) Sec 1-A," Report by Joint Intelligence Staff Unconditional Surrender of Japan, JIS143/2, on April 11, 1945.

Note that there are several documents online titled "Report by Joint Intelligence Staff Unconditional Surrender of Japan" (obviously an important topic at the time to be worth more than one study/take), but with different dates, so those may or may not contain that quote.

And if you wonder why there are several, a 1976 paper explains that

The planners had requested, therefore, on April 7 that the Joint Intelligence Staff (JIS) make an estimate of the resistance that could be expected from Japan to an invasion of Honshu or any of the home islands before unconditional surrender had been obtained. Because it was feared that some Japanese might never surrender, JIS was also asked to evaluate possible resistance after a formal unconditional surrender. These questions led directly to the political aspects of the problem; Japanese appreciation of the unconditional surrender formula. The planners completed their request to JIS by asking:

a) At what stage of the war will the Japanese realize the inevitability of absolute defeat?

b) Will such realization result in their unconditional surrender, passive sub- mission without surrender or continuing resistance until subdued by force?

Three days later JIS replied expressing confidence that the Japanese would recognize defeat by autumn. But the report carefully distinguished between recognition of defeat and unconditional surrender. The literal meaning of unconditional surrender, JIS noted, "is unknown to the Japanese.... Our meaning of the term cannot be comprehended by the vast majority of Japanese." [...]

The members of JIS and particularly the area teams that prepared this general study on Japanese resistance had considerable freedom in making recommendations. They acted within the staff as experts, not as representatives of their departments. It was otherwise in the Joint Intelligence Committee which reviewed their work.

[...] Predictably state department representatives found the study unacceptable. [...] In the presence of this determined protest by state department spokesmen JIS entirely recast the paper, eliminating practically all of the attacks on the unconditional surrender policy.

There was then a JIS143/3 dated April 24, etc.

And another (1995) book of Alperovitz has more extensive quotes from the April 29 version

After consulting with the Joint Intelligence Staff, the Joint Intelligence Committee forwarded its response to the Chiefs in the form of an April 29 “Memorandum for Information.” This pointed out that increasing “numbers of informed Japanese, both military and civilian, already realize the inevita bility of absolute defeat.” It noted, however, that the still indeterminate nature of relations among the Big Three—and of Russia’s role—played a critical role in Japanese judgments. Thus,

military and political authorities, as well as the people generally, may retain the desperate hope that continued resistance will permit the development of such disunity and war-weariness among the United Nations as to enable them to obtain peace without unconditional surrender.

The “Japanese will realize that absolute defeat is inevitable,” the commit­tee advised, “when they perceive that their armed forces are incapable of arresting the progressive destruction of their basic economy.” The committee further advised that:

The increasing effects of air-sea blockade, the progressive and cumula­tive devastation wrought by strategic bombing, and the collapse of Germany (with its implications regarding redeployment) should make this realization widespread within the year.

A Russian decision to join with the United States and Britain, however, would have enormous force and would dramatically alter the equation:

The entry of the U.S.S.R. into the war would, together with the foregoing factors, convince most Japanese at once of the inevitability of com­plete defeat.

which is endnote-cited to

JCS Info Memo 390, “Unconditional Surrender of Japan,” April 29, 1945, “ABC 387 Japan (15 Feb. 45), Sec. i-A ,” Box 504, Entry 421, RG 165, NA.

That book also mentions that

Some of the drafts leading up to this final paper contain additional lan­guage which gives a feel for the developing sense of Japan’s impending collapse among intelligence specialists. For instance, the initial April 11 re­sponse of the Joint Intelligence Staff (a first draft of what became the April 29 Committee report) pointed out that a large number of informed Japanese realized the inevitability of defeat—despite the fact that it was “only very recently that the full power and potential of Allied capabilities are being brought home to the masses of Japanese living in the home islands.”

By the autumn of 1945, we believe that the vast majority of Japanese will realize the inevitability of absolute defeat regardless of whether the U.S.S.R. has actually entered the war against Japan.

And, again, of course: “If at any time the U.S.S.R. should enter the war, all Japanese will realize that absolute defeat is inevitable.'

which citing to JIS143/2 again.

But generally speaking the Alperovitz enterprise in these matters has been severely criticized on other grounds (selective sourcing, ignoring intercepts of Japanese comms during the summer):

The principal rule that Alperovitz broke in 1965, and breaks even more spectacularly in 1995, is the rule that significant contrary evidence must be noted. Essential information is again missing, suggesting the long-term prospects for Alperovitz's thesis are dim at best, fatal at worst. The most disturbing excision is reflected in his claim that the Japanese during the summer of 1945 had reached a "'unanimous determination' to seek surrender through Moscow" (p. 651). What the MAGIC cables in fact reveal is unanimity on the part of the Japanese Cabinet to seek a negotiated peace, and disagreement regarding the terms, even the notion, of surrender. Japanese sources, which Alperovitz uses sparingly, suggest the military was pressing for terms far beyond anything Truman would have accepted, including no American occupation of Japan, exclusive control by the Japanese government over the conduct of war crimes trials, and retention of jurisdiction by Imperial Headquarters over disarmament and demobilization. Such perceptual differences matter not at all to Alperovitz. He uses the terms "seeking peace" and "surrender" interchangeably.


At times written in the tone of an expose, [Alperovitz' book] The Decision to Use the Atomic Bomb is a lawyer's brief, repetitively citing evidence that supports its position, ignoring anything that does not. [...]

  • 1
    Side note: Stalin had agreed to have the USSR join the Allies in their war on Japan three months after the defeat of Germany. This would have placed the USSR joining that war on August 8, later slipped to August 9. Many (not just Aperovitz) have argued that the bombings of Hiroshima and Nagasaki on August 6 and 9 were motivated in part by the anticipated joining of the USSR against Japan. Commented May 21, 2023 at 8:53
  • @DavidHammen And many have argued that it was declaration of war by the USSR which triggered Japan surrender. City bombings, no matter how destructive, had not motivated Germany, the UK, the USSR or Japan to surrender, so it's far from evident why the destruction of Hiroshima or Nagasaki would have moved the Japanese to surrender when the obliteration of Tokyo had not. From their point of view, it didn't matter much if the destruction was accomplished by a single $500M bomb, or $100M in conventional explosive and incendiary bombs.
    – Rekesoft
    Commented May 22, 2023 at 10:09
  • Worth noting that one limitation at the time on nuclear weapons was the time it would take to enrich enough uranium. It was estimated one A-bomb could be made about every 5 months; that's one reason Hiroshima didn't result in immediate surrender; they were like "Okay, but we're safe for a few months now." That was true for uranium, but plutonium addressed this limitation nicely (at the expense of a more sophisticated implosion system). Nagasaki was required to demonstrate that we had solved the refinement issue (or at least amassed a working stockpile). Commented May 22, 2023 at 15:29

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .