Pearl Harbor: the forgotten lesson of soft sanctions

November 11, 2022

We have heard or read a lot about the Japanese attack on the US naval base at Pearl Harbor, but few people know what role oil played in that sad page of the world history.

I suggest starting with the analysis of Japan's energy balance as of 1939. On the one hand, the share of oil in the supply structure of primary energy carriers was less than 10%, but on the other, almost the entire volume was consumed by the navy and the merchant fleet. Domestic production covered about 7%, the rest was imported from the USA, the Dutch West Indies (at that time) and other sources. It is important to note that US oil made almost 80% of Japan's imports. Given such strong dependence of the Japanese economy on the US, official Washington pursued an "open door" policy despite Tokyo's imperial ambitions. Most likely, this foreign policy of the White House was influenced by the worldview of President Roosevelt, who fifteen years earlier wrote a telling article entitled "Can we trust Japan?", where he reflected on the transformation of Tokyo's aggressiveness after World War I.

In reality, it did not part with its aggressiveness, because in late 1930s, the doctrine of Hokushu Nanshin was introduced in Japan. The document provided for active defence on the northern borders (USSR) and offensive actions on the southern borders in order to gain access to oil fields in Indochina. Undoubtedly, such plans also influenced Japan’s energy policy: for example, in 1934, the Law on the Petroleum Industry was adopted, which actually provided for state regulation of the industry through quotas and price fixing for specific suppliers. In addition, Tokyo tried to push out of the domestic mining market the foreign companies Stanvac and Rising Sun, which accounted for 60% in the mining sector.

Such changes in the Japanese legislation prompted the British and US authorities to lobby for an embargo on oil supply. However, all attempts during six years were vain. In addition, the liberal position of President Roosevelt and Secretary of State Hull did not change even after the brutal Japanese bombing of Chinese cities, such as Chongqing. The White House was probably afraid of changes in the Pacific.

The situation changed in the summer of 1940, when Hitler's army occupied Paris and appointed the French puppet government, which allowed introduction of a Japanese military mission to Indochina to effectively control the local oil fields. At the same time, the aggressive rhetoric of Tokyo manifested itself: it issued an ultimatum to Great Britain demanding the withdrawal of its military contingent from Shanghai. Such changes in geopolitics prompted President Roosevelt to sign the National Defense Act of July 2, 1940, which included control over the exports of oil and petroleum products.

Meanwhile, the scope of the sanctions was discussed in July-August. In particular, the Secretary of the TreasuryMorgenthau and the Secretary of Defense Stimson advocated a complete embargo on the US oil supply to Japan. However, the State Department pursued a policy of "soft power and open doors", as was witnessed by the introduction of fairly liberal restrictions that affected aviation gasoline with the octane number of 87 and above. In fact, such restrictions did not affect the combat effectiveness of the Japanese Air Force at all, because their engineers decided to purchase gasoline with a lower octane number and to improve its quality by adding tetraethyl lead. That is why then statistics of US exports shows an increase in the volume of shipments of petroleum products, despite the first wave of so-called sanctions.

Later, in August 1940, Washington imposed a full embargo, but only on steel and iron products. Regarding oil, the US opted to introduce export licenses — rather a flexible tool for limiting oil supply.

At the same time, Japan was actively preparing for the war with the United States and purchasing oil storage tanks. In addition, Japanese naval exercises were conducted close to naval bases in order to save fuel and keep secret the strategic plan of the future military operation, which was planned according to the concept of "one strike" and envisaged a blow on the US Pacific Fleet. The operation was planned by Admiral Yamamoto, who not only paid attention to the art of war but also took account of energy issues. For example, the Japanese military leader sponsored research to obtain oil from water and algae. Such active studies were not surprising, because according to the estimates of then Head of the General Staff Nagano, the Japanese navy would become inoperable in six months after the last shipment of the US oil.

In general, a delay of the decision to introduce a full embargo on oil and petroleum products supply gave the Japanese extra time and resources to prepare offensive actions.

On December 1, 1941, a special unit of the Japanese naval forces crossed the demarcation line and headed towards the Hawaiian Islands in the Pacific Ocean. The attack on Pearl Harbor was only one of the elements of the large-scale offensive campaign by the Japanese army, which included a landing operation in Thailand, as well as the bombing of Hong Kong, Singapore, Thailand.

The ultimate goal of this unprovoked Japanese aggression was to seize the oil fields of the West Indies and to take the Pacific Ocean under control. Implementation of this plan was hindered by the US naval base in Pearl Harbor, which was attacked by the Japanese in two waves.

However, Admiral Yamamoto's plan had a strategic flaw — the US Army's oil tanks in Pearl Harbor were not taken into account. This error in the operation planning made it possible to save almost 5 million tons of oil, without which the US Pacific Fleet would really have been immobilised.

The analysis of these events prompts two conclusions. First of all, the policy of "soft sanctions" cannot repel aggression. Secondly, support and logistics are decisive in a military confrontation.

We believe in the Armed Forces of Ukraine! Let's take care of the energy front!


Maksym Bielawski

Leading Expert, Energy Programmes

Born in 1986 in Zhytomyr oblast


Zhytomyr State Technological University (2008)

Ph.D in Technical Science (2010)

Ivano-Frankivsk National Technical University of Oil and Gas (2012)

Author of 17 patents and 100 scientific works

Work Experience:

2008 – 2011 — Operator of Gas Infrastructure Units, Controller of Gas Transmission System in Rivne Division of PJSC "Ukrtransgas"

2011 – 2017 — Leading Engineer, Deputy Head of Press-Service, Head of Public Relation Department of PJSC "Ukrtransgas"

2017 – 2018 — HR Director of PJSC "Maine Gas Pipelines of Ukraine", Advisor to the Minister of Energy and Coal Industry of Ukraine

2021 — Director of Integrated Communications of NJSC "Naftogaz of Ukraine"