World flags for policy virtually ended oil exports as Japanese assets had been frozen. Soon the British and Dutch East Indies also cut off the flow of oil to Japan. Last-ditch attempts at negotiation failed, leading the Japanese to launch an attack on Pearl Harbor to protect its eastern flank, especially to make tanker routes from Sumatra and Borneo safer. The United States did not, however, simply allow Japanese expansion in Asia. With its greater industrial capacity, including vast oil reserves coming from domestic sources as well as Latin American allies, the United States was able to defeat Japan in 1945. OPEC and oil shocks. In September, 1960, five of the world’s leading oil producers created the ORGANIZATION OF PETROLEUM EXPORTING COUNTRIES (OPEC). World flags 2016.