SDHF Newsletter No.456 Book Review Roosevelt Knew It

< Book Review >
Pearl Harbor Attack: Roosevelt Knew it—15 proofs that overturn
the ‘Surprise’ Attack” theory
Author: Shiramatsu Shigeru; Supervising Editor: Sugihara Seishiro
Publisher: Minerva Shobo, Kyoto, December 8, 2025
Reviewed by: Sugihara Seishiro
March 17, 2016

Whether U.S. President Roosevelt had prior knowledge of the Imperial Japanese Navy’s surprise attack on Pearl Harbor—the event that triggered the outbreak of war between Japan and the United States in 1941 —is a matter of grave significance for both nations.
Despite nine official investigations into this devastating attack—eight conducted during the war and one by a joint committee of the House and Senate immediately after the war—no evidence was found to prove that Roosevelt knew beforehand about the attack.

About 40 years later, using materials from these public investigations, the following two books were published and became widely read in the United States:
・Gordon W. Prange, At Dawn We Slept: The Untold Story of Pearl Harbor, McGraw-
Hill, 1981
・John Toland, Infamy: Pearl Harbor and Its Aftermath, Doubleday, 1982
Although they used the same source materials, their conclusions were diametrically opposed. Prange concluded that not a single piece of evidence was found to support the revisionist position regarding Roosevelt and Pearl Harbor, whereas Toland reached the exact opposite conclusion: that Roosevelt did know. The basis for this was testimony that a wireless operator Z at the 12th Naval District in San Francisco had intercepted a signals transmitted from the Japanese Task Force, pinpointed its location, and reported it to Washington. If this is true, it can hardly denied that Roosevelt knew. However, at that time, according to the Japanese military history study, it was believed that the Task Force that attacked Pearl Harbor maintained strict radio silence. Affected by this theory the wireless operator’s testimony was not fully trusted and although Toland’s theory was widely discussed in the United States, most people regarded it unacceptable.

Ten years afterwards, in 1991, on the 50th anniversary, the U.S. National Security Agency (NSA), with a view to terminating the Roosevelt foreknowledge theory once for all, investing documents declassified before the 50th anniversary of the Pearl Habor attack and concluded that United States Navy could not foresee the surprise attack by the Japanese Navy. However, a book published in Japan in that year The Surprise Attack on Pearl Harbor: Did Roosevelt Know? Written by Konno Tsutomu (Yomiuri Shimbun, 1991), presented a thesis that clearly refuted the U.S. conclusion. Konno investigated each of the seven testimonies which are not direct but supportive evidence of the theory widely spread across the world that Roosevelt knew about the attack in advance and historical value of which cannot be denied. Akonno proved that although those seven testimonies describe separate situations, on close examination of each of them, theory fit into one pattern and align with each other beyond time and space. In particular, regarding the account in Toland’s book that wireless signals from the Task Force were detected, allowing its position to be determined and reported to Washington, Konno’s book explained this phenomenon using the theory that if the Task Force had spread out across the Pacific to a width roughly equivalent to Awaji Island, radio waves transmitted from Funabashi toward the Task Force would be reflected by the Task Force as if by a mirror, creating the effect that new radio waves were being transmitted from that location.

Ten years later, in 2000, a scholarly work titled Day of Deceit: The Truth about FDR and Pearl Harbor by Robert Stinnett was published by Free Press. With the release of relevant Navy documents, research into the “foreknowledge theory” began to take a new turn. Stinnett gained access to the Navy’s records of intercepted Japanese naval radio transmissions regarding Pearl Harbor. He revealed that the Japanese Navy’s movements were clarified to considerable extent but they were not informed to the base in Pearl Harbor. The radio operator identified by Toland as Z was named Robert Og, and the book includes original documents showing that he had intercepted radio transmissions sent by the Task Force. Toland’s claim was correct.

Twenty-five years later, in 2025, Shiramatsu Shigeru of Japan gained access to materials that even Stinnett had not accessed or analyzed, and revealed that the D-code—which the Japanese Navy had used in the belief that it was indecipherable—had in fact been deciphered to a certain extent. He published this book, Roosevelt Knew it. Of which book review was written by Sugihara Seishiro, the editor of that book.

Along with the “foreknowledge theory,” an important argument raised by Shiramatsu concerns why the Chicago Daily Tribune reported on December 4—three days before the Pearl Harbor attack—about the Roosevelt administration’s war plan to mobilize 10,000,000 strong. This should have put Roosevelt in a dire predicament, but in fact, it was a deliberate leak orchestrated by Churchill and approved by Roosevelt. The purpose was to ensure that Germany—which had no obligation to join the war after it broke out—would inevitably decide to declare war on the United States. The calculation was that if Hitler became aware of such a massive war plan, he would conclude that war with the United States was inevitable. He would then reason that, since the U.S. preparations were not yet complete, he had no choice but to declare war at that very moment. Thus, it was anticipated that Hitler would go ahead and declare war on the United States. After agonizing over the decision, Hitler declared war on the United States on December 11.
　This is the first book in Japan to introduce mechanism of the leaking incident. Thus, the “foreknowledge” has been fully proven, too.
　　
Original Japanese Book Review:　https://hassin.org/01/wp-content/uploads/Pearl.pdf
English Translation of Japanese Book Review: https://www.sdh-fact.com/CL/PearlE.pdf

Moteki Hiromichi, Chairman
Society for the Dissemination of Historical Fact