September 24, 1941: Japanese Spying Intensifies

Wednesday 24 September 1941

Citizens of Leningrad construct a defense barricade near the Kirov Factory No. 100, 24 September 1941

Spy Stuff: Japanese spying in the United States is a fact, and on 24 September 1941 it shifts into a higher gear. The Japanese Foreign Ministry sends its consulate general in Hawaii, Nagai Kita, instructions in Telegram No. 83 to ramp up his spying efforts. The Consul is to divide Pearl Harbor into five different spy zones:

Henceforth, we would like to have you make reports concerning vessels along the following lines insofar as possible: 1. The waters (of Pearl Harbor) are to be divided roughly into five sub-areas. (We have no objections to your abbreviating as much as you like.) Area A. Waters between Ford Island and the Arsenal. Area B. Waters adjacent to the Island south and west of Ford Island. (This area is on the opposite side of the Island from Area A.) Area C. East Loch. Area D. Middle Loch. Area E. West Loch and the communicating water routes. 2. With regard to warships and aircraft carriers, we would like to have you report on those at anchor, (these are not so important) tied up at wharves, buoys and in locks. (Designate types and classes briefly. If possible we would like to have you make mention of the fact when there are two or more vessels alongside the same wharf.)

These new instructions are a reflection of the increased pace of planning in the Japanese Navy for an attack on Pearl Harbor.

"ATS anti-aircraft artillery spotters learn to use an identification telescope at No.7 ATS Training Centre at Stoughton near Guildford, 24 September 1941." (© IWM (H 14189)).

The Japanese have been spying on US Navy activities both in Honolulu and in the Philippines for months. In fact, they have gone to the extent of putting a specially trained expert in military espionage on the staff of the Honolulu Consulate. In a 17 September 1941 cable from Santiago to D.C., the Japanese Embassy was instructed:

All of our offices in North America should give their immediate attention to the selection of spies.

So, while today's development marks a new phase in the degree of Japanese spying, it is not a completely new tactic. Rather, it is an extension of a growing attempt by the Japanese to develop intelligence that would be useful during a conflict with the United States.

Pearl Harbor drydocks on 24 September 1941. USS Utah (AG-16) is barely visible under the steel bridge in the background (National Archives).

There is spying going on by both sides. While the Japanese are spying on the US military in Hawaii, the Americans are reading the Japanese diplomatic code J-19 under which the spy reports are sent to Tokyo. The United States naval intelligence intercepts the instructions to Consul Kita, but the intercepted message must be sent to Washington to be decoded. This being spy stuff, the intercepted message can't just be sent by cable lest the Japanese intelligence services intercept the intercepted message in turn and realize their own codes are being read (the spy business gets very complicated sometimes). So, the transmission must be hand-carried and hand-delivered and generally treated with extreme care. There aren't any flights, so the courier goes by sea. Once the message gets to Washington, there aren't enough experts to decode it quickly. The whole process becomes a sort of "comic opera" version of spying.

Lt. Hans-Joachim Marseille of  3./JG 27 shoots down five RAF planes today in North Africa. They are his 19th through 24th kills, four Hawker Hurricanes and a Martin Maryland bomber.  

The end result is that the transmission isn't actually decoded by the "Magic" cryptanalysis project until 9 October 1941. Two of the Magic experts then find the message to be concerning and submit separate assessments to that effect. However, their superiors in the War Plans and Intelligence Divisions in Washington don't read anything sinister into the heightened spying efforts. Instead, the Magic staff just use the intercept to make some essentially literary criticisms of a Japanese tendency to pay too much attention to details. Pearl Harbor is never even notified that the Japanese are spying or warned that this might mean something for the future.

Linda McCartney, born on 24 September 1941.

Future History: Linda Louise Eastman is born in New York City to a father of Jewish Russian descent and a mother of German Jewish descent. Linda studies at the University of Arizona, where she develops an interest in photography. She becomes a top photographer of rock stars in England. There, Linda meets Paul McCartney and they get married in 1969. Later, Paul and Linda form rock group Wings in the 1970s and Linda participates in recordings with Paul McCartney then and later. Linda McCartney passes away from breast cancer on 17 April 1998.

Two young girls with three dogs at a Sears Roebuck store at 1148 Broadway in Manhattan, New York. This photo was taken to promote National Dog Week.

September 1941

September 1, 1941: Two Years In
September 2, 1941: Germans Pushed Back at Yelnya
September 3, 1941: FDR Refuses to Meet with Japanese
September 4, 1941: Hitler Furious at Guderian
September 5, 1941: Germans Evacuate Yelnya
September 6, 1941: Japan Prepares for War
September 7, 1941: Hitler Orders Drive on Moscow
September 8, 1941: Leningrad Cut Off
September 9, 1941: Germans Attack Leningrad
September 10, 1941: Guderian Busts Loose
September 11, 1941: Convoy SC-42 Destruction
September 12, 1941: Starve Leningrad!
September 13, 1941: Zhukov at Leningrad
September 14, 1941: Germany's Growing Casualties
September 15, 1941: Sorge Warns Stalin Again
September 16, 1941: Soviets Encircled at Kiev
September 17, 1941: Iran Conquest Completed
September 18, 1941: Focke-Wulf Fw 190 in Action
September 19, 1941: Germans Take Kiev
September 20, 1941: Death at Kiev
September 21, 1941: Raging Soviet Paranoia
September 22, 1941: Defense of Nickel Mines
September 23, 1941: Air Attacks on Leningrad
September 24, 1941: Japanese Spying Intensifies
September 25, 1941: Manstein at the Crimea
September 26, 1941: Kiev Pocket Eliminated
September 27, 1941: Massacre at Eišiškės
September 28, 1941: Ted Williams Hits .400
September 29, 1941: Babi Yar Massacre
September 30, 1941: Operation Typhoon Begins

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