Interestingly, it was the threat of an oil embargo (and an actual scrap iron embargo) by FDR in 1941 that is seen by many as the trigger for Pearl Harbor. At the time, the US was the world's largest producer and exporter of oil. A full blockade of Japan's major ports was in place by the fall of 1944. Indonesia was their last hope for oil; here's some history:
http://www.gimonca.com/sejarah/sejarah07.html