The Raid

Four months after the devastating air attack on Pearl Harbor the US struck back at Imperial Japan. On April, 18, 1942 sixteen B-25 Army Air Corps B-25 medium bombers, in the “first air operation to strike the Japanese archipelago,” bombed targets in five cities – Tokyo, Yokohama, Yokosuka, Nagoya, and Kobe.(1)  The raid caught the Japanese by surprise and killed about 50 people and injured some 400.(2)

The Plan

“President Franklin D. Roosevelt expressed to the Joint Chiefs of Staff in a meeting at the White House on 21December 1941that Japan be bombed as soon as possible…”(3)  The man put in charge was Lieutenant Colonel Jimmy Doolittle, a renowned aviator. His concept was to use Army Air Corps Mitchell B-25 medium bombers, launched from the aircraft carrier USS Hornet, to strike at the heart of the Japanese Empire. The B-25 were modified to carry twice the normal fuel load in order to fly westward to China and later form the nucleus of a bomber capability for Claire Chennault’s Flying Tigers.

“Doolittle ordered target maps of the area’s iron, steel, and aluminum industries as well as aircraft plants, shipyards, and oil refineries…”(4)  Knowledge of the planned raid rapidly spread. The Nationalist Chinese were informed so as to prepare landing sites in China but were not told that the aircraft would bomb Japan beforehand. “Negotiations with the Soviet Union for permission to land were fruitless because it had signed a neutrality pact with Japan in April 1941… [and] Stalin was not in a position to provoke Japan…”(5)

A significant source of intelligence came from Navy Lieutenant Stephen Jurika, Jr. Schooled in Kobe and Shanghai, he spoke Filipino, Spanish, Japanese, and Chinese as well as English. As the intelligence officer onboard USS Hornet he briefed the crews what to expect and how to request help if forced down in China. He had arrived as assistant Naval Attaché in Japan in 1939 and soon realized that the US had no target maps of Japan. He collected detailed land maps. He befriended the assistant Soviet naval attaché, Ivan Egoricheff, who already had much of the information Jurika sought and provided it.(6)

The plan was to approach to 400 the Japanese coast, take o) just before dark, bomb at night, and proceed to China by early morning. However, as Doolittle reported later the first enemy patrol vessel was detected. and avoided at 3:10a.m. on the morning of April 18. The Navy task force was endeavoring to avoid a second one sometime after daylight when they were picked up by a third. Although this patrol was sunk it [was] understood that it got at least one radio message off to shore.”(8)  This was detected by the Navy’s radio intercept operators onboard USS Enterprise, which accompanied USS Hornet.

As a result, Admiral Halsey, the Task Force 16 commander, decided to launch the strike immediately, some 250 miles further away than planned. Doolittle’s aircraft (No. 40-2344 took off at 08:20; the last (No. 40-2268) at 09:19.  This put all planes over their targets in daylight. See Figure below.

Targets

Specific targets were assigned each of the six-teen B-25 crews once at sea. They were provided target folders and maps. (9)  Ten aircraft were destined for Tokyo, two each to Yokohama and Nagoya, and a single plane to Yokosuka and Kobe. Planning for the raid was accomplished in three months. In many ways the US military was unprepared. As Doolittle reported afterwards “… navigators had had good training but very little practical experience.” “Celestial navigation practice for our navigators [was] supervised by the Hornet navigation officer when already at sea. But it was successful as “… through the use of the airplane compass and directional gyro [which] permitted the establishment of one accurate navigational course and enabled us to swing o) on to the proper course for Tokyo.” (10)  Geographical intelligence was described as deficient. “The maps which we used were misleading because the contour interval was too great.”(11)  “Our charts were found to be unreliable as to details”(12)  and “… inaccuracies in representation of topography by Japanese Naval Air Charts made pilotage extremely difficult.”(13)

“The best information available from Army and Navy intelligence sources indicates that there were some 500 combat planes in Japan and that most of them were concentrated in the Tokyo Bay area.”(14)  

Despite largely anemic attacks by Japanese fighters and inaccurate anti-aircraft artillery ‘re over the target cities, most of the primary targets were struck. (15)  See figure blow.

Doolittle’s immediate assessment was a “high degree of damage”(16)  Historians note that despite pilot reports of major damage to selected targets, “the raid caused negligible damage… but had major psychological effects.”(17)

What the Japanese Knew Beforehand

It is unknown whether the Japanese, who had broken several Chinese and Russian codes, as well as US diplomatic codes, gained any foresight through intercepting communications before the raid. Apparently, Admiral Yamamoto, based on Japanese signals intelligence, was apprehensive of an American air raid on Tokyo.(18)  The raid was shrouded in secrecy, however, the Japanese were alerted to Task Force 16 (19) “Japanese submarines detected its presence northwest of Hawaii on 10 April and Japanese radio intelligence reported its probable intentions on the on the 14th …”(20)  “The Japanese, through a small amount of intercepted radio traffic between [Admiral] Halsey [on USS Hornet] and [Captain] Mitscher [on USS Enterprise], were aware that an American carrier force was at large in the Western Pacific Ocean and could possibly attack Japan.”(21) Then at “07:38 on the morning of 18 April, while the task force was still about 650 nautical miles(1,200 km; 750 mi) from Japan (around 35°N, 154°E), it was sighted by the Japanese picket boat No. 23 Nitto Maru, a 70-ton patrol craft, which radioed an attack warning to Japan. The boat was sunk by gun fire from USS Nashville.“ (22)  As Doolittle noted “… even at this distance from Japan the ocean was apparently studded with Japanese craft. “(23)


“The Japanese… deduced that a carrier raid on the homeland was a possibility after 14 April 1942 and prepared accordingly.” But “[l]acking radar, the Japanese ‘early warning’ capability lay in parallel lines of picket boats—radio equipped converted fishing trawlers—operating at prescribed intervals o)shore.” “The Japanese 26th Air Flotilla, expecting the Americans to approach within 200 miles of Japan as they had done in the raids in February in the Marshalls and Gilberts, and Wake and [in March] at Marcus, launched29 medium bombers equipped with torpedoes from Kisarazu, escorted by 24 carrier fighters equipped with long-range tanks, to find TF-16.” “Search efforts continued, without success, until 24 April.” (24)  “[K]nowing the short range of American carrier aircraft, the Japanese assumed that the US task force would not be within range of Japan until the following day, April !#, which would allow ample time for interception. (25)  The use of long range Army bombers was unanticipated.

American carriers were too few and too precious to risk in waters close to Japan. Task Force 16 had a radio intelligence unit embarked on the USS Enterprise, which escorted the USS Hornet with Doolittle’s B-25 to provide air cover as the B-25 arrayed on the deck prevented the launching of Hornet’s own fighters. As reported by the unit “our primary mission was to inform the Task Force Commander when we were spotted by the enemy. After the planes had left, we watched the Empire search planes’ frequencies, mostly concerned with the Kisaratsu Air as he controlled the search planes. The enemy knew the general area we were in, but fog and overcast prevented them from finding us even though they were all around the task force.”(26)  This intercept team was a critical intelligence support element.

It is not apparent that Task Force 16 received direct support from Station Hypo, the Navy’s cryptologic unit in Hawaii. At this time most of its focus was on the southwest Pacific and the Japanese offensives against New Guinea and other islands near the Coral Sea.(27)  US Navy intercept operators in Hawaii “weren’t able to intercept everything. Many messages were missed… Hypo was limited in the volume of signals it could intercept by technology and manpower… [and] lacked sufficient men and machines to listen to every relevant frequency used by the Imperial Navy.”(28)

Aftermath

Despite the Japanese having early warning the “task force enjoyed the element of complete surprise.”(29)  However, all of the B-25 involved were lost when out of gas the crews bailed out along the China coast. Three crewmembers died. Eight were captured; three of which were executed as war criminals by the Japanese and another died in captivity. One aircrew, which recovered in the Soviet Union, was interned for a year before “escaping” to Iran.

And while the physical bomb damage was inconsequential to Japan’s war effort, the psychological impact was great. “Several false alarms followed”30  “The raid shook staff at Japanese Imperial General Headquarters. “(31) “It caused the Japanese to question their warlords” was Doolittle’s judgment.*%

The Japanese high command withdrew a substantial number of aircraft from supporting offensive operations in the southwestern Pacific, Indochina, Indonesia, and China in order to defend the home islands. Japan retaliated against China as it “felt compelled to… save face and prevent future attacks on the homeland by ruthlessly eradicating any threat of future raids emanating from Chinese airfields>”(33)  “Japanese reprisals caused the deaths of 250,000 civilians and 70,000 soldiers…” including an estimated 10,000 Chinese civilians during their initial search for Doolittle’s aircrews.(34) The Japanese campaign lasted three months.

The Japanese had decided on April 16 – two days before Doolittle’s raid – to seize Midway Island. (35)  The IJN’s “… preparations [for Midway] were interrupted momentarily by the Doolittle raid and the subsequent attempts to find the American carriers.”*- Some believed that Doolittle’s bombers had originated from Midway or from the Aleutians. It likely strengthened Admiral Yamamoto’s determination to capture Mid-way. *. He had set his sights on Midway and its airfield as early as February 1942. (38)

In the dark days of early 1942, Doolittle’s Tokyo raid was the first victory America had achieved in the war. It dominated the front pages of American newspapers and boosted morale in the US and with American allies. He was awarded the Medal of Honor. All of the seventy-nine others received the Distinguished Flying Cross.

The raid had a little-known strategic impact. “Before the Doolittle mission, the [IJN] was observing near radio silence, frustrating the e)orts of American cryptographers, who had deciphered only about 10 percent of the Imperial Navy’s code book. The stunning airstrike at the heart of Japan unleashed a torrent of coded messages, so that within a few weeks American codebreakers had cracked nearly 90 percent of the Japanese naval code.”(39) The impact of that was felt in less than two months at the Battle of Midway.

Footnotes:

1. “Eighty Brave Men” (http://www.doolittleraider.com/80_brave_men .htm).
2. Carroll V. Glines. The Doolittle Raid: America’s Daring First Strike Against Japan. Afglen, PA: Schi#er Publishing. 2000 (First published in 1988).
3. Glines, p 166-168
4. James M. Scott. Target Tokyo: Jimmy Doolittle and the Raid that Avenged Pearl Harbor. New York: W.W. Norton & Company, 2015, p 62.

5. General Doolittle’s “Report on Japanese Raid to the War Department, 9 July  1942” http://www.ibiblio.org/hyperwar/AAF/rep/Doolittle /Report.html.
6. Scott, p 141
7. The craft were detected by the USS Enterprise’s radar. At the time few US Navy ships had radar, which was a new technology.
8. Doolittle Report. In his book Scott states the Nitto Maru No. 23 sent the radio message: “Three enemy carriers sighted. Position (600 nautical miles east of Inubosaki.” P 172-3. It continued radio transmissions for 27 minutes after USS Nashville’s first shots. It was finally sunk at 0821. P 175
9. Doolittle Report.

10. Ibid.
11. Report of Airplane No. 40-2297 to Doolittle by pilot – Major John A. Hilger.
12. 1st Lt James H. Macia, navigator. Appended to Doolittle Report.

13. 2nd Lt. Eugene F. McGurl. Appended to Doolittle Report.

14. Doolittle Report.
15. Each plane carried four 500 pound bombs usually a combination of high explosive demolition bombs and incendiary cluster munitions.
16. Doolittle Report.
17. http://www.historynet.com/aftermath-doolittle-raid-reexamined.htm. Scott in his book writes that many of the crews missed their intended targets.

18. Scott, p 189
19. TF 16 was a large operation. It consisted of 2 carriers – Hornet (CV-8) and Enterprise (CV-6; 3 heavy cruisers – Salt Lake City, Northampton, Vincennes; 1 light cruiser – Nashville; & destroyers – Balch, Fanning, Benham, Ellet, Gwin, Meredith, Grayson, Monssen; and ” oilers – Cimarron, Sabine.
20. Parker, p36
21. Wikipedia, The Doolittle Raid, footnote #(%, citing Glines, p 60-2.
22. Glines, p 70
23. Turning Point: The Doolittle Raid. The National WW II Museum.
24. Naval Historical and Heritage Command, Doolittle Raid, 18 April 1942. Published May 10, 2019. https://www.history.navy.mil/browse-by-topic/wars-conflicts-and -operations/world-war-ii/1942/halsey-doolittle-raid.html.
25. Michael Peck. “30 Seconds Over Tokyo: How the Doolittle Raid Doomed the Japanese Empire,” The National Interest, 2019.
26. Memorandum for Commander P.P. Leich, USNR, Subj: Task Force Sixteen (USS Enterprise – Flag), from H. A. Cain, CRE, USN. S E C R E T (Declassified), 10 September 1945. Reprinted by Station Hypo as “How Radio Intelligence Supported the Doolittle Raid, 18 April 2-19. https://stationhypo.com/2019/04/18/how-radio-intelligence-supported-the -doolittle-raid/#more-11421.
27. The Battle of the Coral Sea was to take place less than a month after Doolittle’s raid on 4-8 May 1942.
28. Elliot Carlson. Joe Rochefort’s War: The Odyssey of the Codebreaker Who Outwitted Yamamoto at Midway. Annapolis, MD: Naval Institute Press. 2011. P 273.
29. Parker, p 36
30.  Robert Craigie. Behind the Japanese Mask. London: Hutchinson & Co., 1945. Pp 147-7
31. Wikipedia citing “War in the Pacific: View from Japan,” Bungei-shunju,1994. Author unknown.

32. Interview with Gen. James H. Doolittle. Published July 16, 2015. https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/FactSheets /Display/Article/196771/interview-with-gen-james-h-doolittle/.
33. Chris Byrd. “Bombers over Tokyo: The Strategic Importance of Doolittle’s Raid,” The Bridge https://www.realcleardefense.com/articles/2018/04/18/bombers_over _tokyo_the_strategic_importance_of_doolittles_raid_113340.html.

34.  http://www.historynet.com/aftermath-doolittle-raid-reexamined.htm.
35. Parker, p 36.
36. Parker, p 36.

37. Glines emphasizes this theory. Admiral Nagumo, who led the Pearl Harbor attack, called Midway “the sentry for Hawaii.” (Scott, p 136
38. Turning Point: The Doolittle Raid. The National WW II Museum.

39. Winston Groom. Trained in Secret, these Fearless Pilots Retaliated for Pearl Harbor, National Geographic. https://news.nationalgeographic .com/2017/04/doolittle-raiders-anniversary-world-war-two-history/.

By Peter C. Oleson, senior editor of Intelligencer

This article is drawn from the series “When Intelligence Made a Difference,” published by the Association of Former Intelligence Officers.  The series is on-line and free to use at https://www.afio.com/22_intelligencer.htm#WIMAD.”