
As the United States commemorates the 76th anniversary of the Japanese surprise attack against the U.S. naval base at Pearl Harbor on December 7, 1941 few people know that Japanese war plans were inspired by a 1925 novel titled The Great Pacific War, written by the British author Hector Bywater.

The novel predicted a Japanese surprise attack on U.S. naval forces in the Pacific, the Allies’ island hopping strategy used during the actual Pacific War, and the eventual U.S. victory over Japan. Bywater’s work of fiction is thought to have influenced Imperial Japan’s chief naval strategist and commander of the Imperial Navy’s Combined Fleet, Marshal Admiral Isoruko Yamamoto, when he was planning his naval campaign against the United States.

Hector Bywater was one of the preeminent naval analysts of his day. After working for British intelligence prior to the outbreak of World War I, he published Sea Power in the Pacific: A Study of the American-Japanese Naval Problem in 1921, in which he outlined the growing naval competition between Japan and the United Stated in the Pacific region. He rose to further public prominence with his expert coverage of the Washington Naval Conference, held between 1921 and 1922, predicting, among other things, Japan’s official positions on naval armament before they were made public.

In 1925, Bywater published The Great Pacific War expanding on his ideas about a future clash between Japanese and U.S. naval forces first outlined in Sea Power in the Pacific. The novel takes place in 1931 and begins with a suicide attack by a Japanese freighter that blocks the Panama Canal and is followed by a surprise attack by the Japanese Imperial Navy against the U.S. Pacific Fleet off Manila Bay, the seizure of the Philippines and Guam next to other territories, as well attacks and raids of Hawaii and the U.S. West Coast by Japanese submarines and seaplanes.

The war ends after six years of heavy fighting, during which the Americans slowly encroached on Japan by employing a leapfrogging strategy. In the book, U.S. naval forces defeated the Imperial Japanese Navy in a climactic battle off the island of Yap in the Western Pacific. In the battle, the Japanese lose five battleships while the U.S. Navy loses only two. Japan finally capitulates following a U.S. air raid on Tokyo where U.S. aircraft drop bombs filled with leaflets urging the Japanese population to surrender rather than risk destruction of their homeland.

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It is important to emphasize that the novel does not describe an attack on Pearl Harbor, given that the naval base there had not been developed to accommodate a large fleet when Bywater wrote The Great Pacific War. Bywater did not anticipate the importance of aircraft carriers and air power in general, although carrier-based aircraft feature in the novel. (His climactic final battle of the war was still fought between capital ships.) He also did not foresee the importance of the torpedo and submarines in naval warfare. Furthermore, he wrongly, as it turned out, expected the use of chemical weapons in the fictional war.

Bywater’s novel was popular in the 1920s and 1930s. While he was based in Washington D.C. as a naval attaché from 1926 to 1928, Isoruko Yamamoto read it with great interest, as William H. Honan notes in his book Visions of Infamy: The Untold Story of How Journalist Hector C. Bywater Devised the Plans That Led to Pearl Harbor. Bywater and Yamamoto met several times. In 1934, Bywater interviewed Yamamto in London, who in turn questioned the novelist extensively on naval strategy. (Yamamoto purportedly agreed with Bywater’s assessment that Japan could not hold out for more than 18 months in a war with the United States.)

The book was translated into Japanese and for a time became required reading for Japanese Navy officers (in the United States, war planners purportedly rewrote War Plan Orange to more closely resemble the operational plan described in the novel.) According to Honan, Yamamoto read Bywater’s novel “so assiduously in both overall strategy and specific tactics at Pearl Harbor, Guam, the Philippines, and even the Battle of Midway that it is no exaggeration to call Hector Bywater the man who invented the Pacific War.” This almost certainly overstates the novel’s influence.


For one thing, many other analysts and naval planners were anticipating a future military confrontation between the two countries in the Pacific. For example, the German writer Karl Haushofer in a 1922 study discussed similar possibilities and also pre-shadowed the Allies’ island hopping campaign. Furthermore, Japanese planners scarcely needed Bywater’s novel to recognize the military benefits of a surprise attack. After all, surprise attacks had worked for the Japanese in the first Sino-Japanese War in 1894 and in February 1904 when the Imperial Japanese Navy destroyed the Russian Far East Fleet anchored in Port Arthur. Indeed, Yamamoto lost two fingers during the battle of Tsushima in 1905, a major naval engagement of the Russia-Japanese War.

Nonetheless, although the book likely did not cause Yamamoto to plan a surprise attack on U.S. forces, a strong argument can be made that the novel reinforced Yamamoto’s already held conviction — largely the result of quick victories during the First Sino-Japanese War and Russia-Japanese War — that a decisive battle between surface fleets might still produce a favorable strategic outcome for Japan even against a superior enemy like the United States. As I wrote in the September 2017 issue of The Diplomat Magazine:

What is often misunderstood is that the commander of the Imperial Navy’s Combined Fleet, Admiral Isoroku Yamamoto, did not believe that he would annihilate all U.S. naval power in the Pacific at Pearl Harbor in December 1941. Rather, Yamamoto saw the raid on Pearl Harbor as a means to sharply reduce American combat power before U.S. naval forces would finally be destroyed closer to Japan, most likely in the Philippine Sea, by new Yamamoto-class superbattleships. In short, Pearl Harbor was part of a sea battle concept that called for “progressive reduction operations” against the U.S. Navy before the main fleets of battleships would meet. (…) Although Yamamoto clashed with other naval officers over his daring aircraft carrier raid on Pearl Harbor, decisive naval action fought by battleships remained the non-plus ultra for Japan’s senior naval leadership. The Japanese Imperial Army would play only a secondary role in this plan with its primary task holding on to the outer defense perimeter. Pearl Harbor was meant to give the army a year to transform the newly conquered territories into bulwarks against U.S. counterattacks. However, as is turned out, it would not succeed in doing so because of logistical difficulties (…).

Interestingly, the Philippine Sea is precisely where Bywater’s first naval battle between Japanese and U.S. forces also takes place in the novel. Furthermore, like Japan’s chief naval strategist, the author focused on decisive battles fought between capital ships as the ultimate deciding factor in his fictional war.

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The fact that Yamamoto’s war plan shared a lot in common with Bywater’s strategic thinking and his general outline of a future Japanese-U.S. conflict could therefore be interpreted as a curious case of cross-cultural group thinking. It could also merely illustrate that there are always a finite number of possible strategies and counter-strategies in war restricted by the prevailing military thought of the time.

What ultimately convinced Yamamoto to use aircraft carriers and airplanes armed with torpedoes to strike the U.S. fleet anchored in Pearl Harbor was the Battle of Taranto in November 1940, during which obsolete British Fairely Swordfish biplane torpedo bombers, launched from an aircraft carrier, managed to sink one Italian battleship and heavily damage two more. Consequently, rather than art imitating life, as the axiom goes, life seems to have imitated life on the morning of December 7, 1941 at Pearl Harbor.