During World War II, the 315th Bomb Wing, Twentieth Air Force, was assigned the task of destroying the oil refining capacity and oil storage facilities of Japan) After careful analysis and evaluation, the Strategic Intelligence Section of the Air Staff in Washington, D.C. concluded that destroying the Japanese petroleum industry would produce an immediate effect on the tactical situation in the Pacific Area of Operations. The Joint Chiefs of Staff believed that aerial bombardment of Japanese refineries would deprive them of critically needed crude oil and gasoline and would shorten the war. Gen. Carl A. Spaatz, commander of the U.S. Strategic Forces in Europe had seen Germany's ability to wage war severely damaged by the strategic bombing missions against the German oil industry. Later, when he assumed command of the U.S. Army Strategic Forces in the Pacific, Spaatz supported the plan to destroy Japan's petroleum industry, as did Maj. Gen. Curtis E. LeMay, commander of the Twentieth Air Force, and Brig. Gen. Barney Giles, the deputy commander.
Between June 26 and August 14, 1945, the 315th Bomb Wing carried out fifteen bombing missions against Japanese oil refineries and inflicted heavy damage upon the petroleum industry. After reviewing the post-strike photographs of the air attack on one target, the Maruzen Oil Refinery at Shimotsu, General LeMay wrote to the Wing Commander, Gen. Frank Armstrong, "you achieved ninety-five percent destruction, establishing the ability of your crews with the APQ-7 to hit and destroy precision targets, operating at night. This performance is the most successful radar bombing of the Command to date."
The United States Strategic Bombing Survey (USSBS) reports that, "the bombing offensive against the Japanese oil industry did not begin until May 1945. By that time the blockade had achieved its maximum effect and the refineries were largely inactive for lack of crude oil. Many tank farms were completely empty when bombed.... " (2) Elsewhere, the Survey states that, "the total amount of oil stocks destroyed between May 1945 and the end of the war amounted to 471,379 barrels (19,797,918 gallons)." (3) These figures are very close to the cumulative data obtained for the oil destroyed in bombing missions from May to August 1945, shown in Table 1. These data indicate that 471,341 barrels (19,796,322 gallons) of crude oil, aviation gasoline, motor gasoline, kerosene, gas oil, diesel fuel, fuel oil, aviation lubricating oil, other lubricating oil and miscellaneous oil products were destroyed. In July and August, the last two months of the war, 164,082 barrels (6,891,444 gallons) of oil supplies were destroyed in the bombing campaign.
In Chapter 4 on The Air Attacks and Their Effectiveness, the USSBS reports,
At the Akita refinery of the same company (Nippon Oil Co.) 12,000 100 and 250 pound bombs were released over the target during the last raid of the war. Over 1,200 of them fell into the refinery and oil storage areas. The refinery was in full operation, with furnace fires lighted and equipment filled with oil; a storage area located on a rise of ground adjacent to the refinery contained steel tanks partially filled with oil.... The burning oil from the ruptured tanks in the storage area flowed over the operating section, utterly ruining it. (4)
A review of the data on crude oil production and refining in the U.S. Strategic Bombing Survey reveals some inconsistencies, as the ones cited above, and leads to an entirely different conclusion than was reached by the authors of the Survey with regard to the availability of oil at Japanese refineries during the Twentieth Air Force's bombing offensive in 1945.
It appears that various authors (5), perhaps relying on the conclusions of the U.S. Strategic Bombing Survey, have also reported that the bombings of the Japanese oil refineries were futile and unnecessary because there was no oil to destroy at these installations. For example, Bradley (6) reports, "The efforts, however, was criticized by the USSBS. It states that the Japanese were refining virtually nothing by the time the bombing effort started since the blockade had cut off its supply of crude oil from the Netherlands East Indies and the Asian Continent." "Our target selection of the oil industry for the 315th Bomb Wing could be faulted, since it was hitting an already dead industry as a result of the naval blockade and B-29 mining campaign." Historian Kenneth Werrell wrote,
Despite its great success, Eagle [radar] did not help the war effort. There was no point in destroying Japan's oil plants since their production had peaked between July and September 1943, well before the Boeing B-29 Superforts began their bombing campaign. It was the cutting of the oil imports, not the bombing of the refineries that throttled Japanese fuel.... The bombing destroyed 85 percent of the industry, yet contributed little to ending the war since the facilities were essentially closed down for lack of crude oil. (7)
In his book, Downfall-The end of the Imperial Japanese Empire, Richard Frank writes, "LeMay assigned the 315th the mission of destroying the Japanese petroleum industry. But ultimately this was the least effective component of the strategic attack upon Japan because the loss of these processing facilities had almost no impact due to the overall lack of crude oil to refine." (8) J.B. Smith, in his account of The Last Mission flown by the 315th Bomb Wing, reports that "By 1 April  the Allied blockade had effectively shut off all of Japan's foreign oil supply. By the time we began our missions Japan's oil output had been reduced to 3 or 4 percent of its normal refinery yields. Little fuel was being produced domestically, and no supplies were coming from the Southeast. The storage tanks were mostly empty." (9) Professor Jerome Cohen provides a scholarly review of Japan's economy during the war and reconstruction, with a useful discussion about the role of oil but, he, too, reflects the view set forth in the USSBS, "Seven percent of all U.S. bombs dropped on Japan fell on the oil industry. Every important refinery on Honshu was hit; 85 percent of the total capacity was rendered inoperative but for the most part the bombs fell on inactive plants." (10)
While these authors wrote that the Japanese oil refineries and storage facilities did not qualify as strategic targets, because they lacked significant quantities of crude oil and petroleum products the debriefing verbal accounts by the combat crews who flew the oil missions against the Japanese refineries reported raging fires after the bombing runs, fires being fed by the petroleum supplies contained in the refineries. This discrepancy led to a research project whose purpose was to verify or disprove the claim that "there were no strategic oil targets left to destroy in Japan in 1945." Relying on quantitative data obtained from the United States Strategic Bombing Survey, the Nippon Oil Company, the Japan Statistical Yearbook (1950) (11), the Geological Survey of Japan (12) and other publications this paper examines these claims about the lack of oil at Japanese refineries and finds them to be unsubstantiated and incorrect.
Nippon Oil Company Data
After more than a year of correspondence and communication with various Japanese organizations (including the Petroleum Association of Japan, the Japan National Oil Corporation, the Petroleum Department of the Ministry of International Trade and Industry, the Japanese embassy in Washington, and the Japan Technical Information Group), quantitative data on crude oil and processed by-products were obtained from the Nippon Oil Company for the period April to September 1945. Table 2 lists the crude oil throughput at nine of the Nippon Oil Company refineries. The original data (in kiloliters), have been converted to U.S. gallons and both sets of data are presented. Of the nine refineries listed, data were furnished for the six refineries located on the Japanese mainland (Kashiwazaki, Niigata, Akita, Yokohama, Kudamatsu and Hokkaido). The data reveal that there were inventories of crude oil at all of these refineries and, in some, significant quantities. (No data were provided for the refineries at Tsurumi and Kansai.) The facility on Taiwan was the...