Why was japan so desperate for oil? (what did it use oil for?)

After Hitler invaded Russia in June 1941, Japan moved into southern Indochina. FDR ordered all Japanese assets frozen. But FDR did not want to cut off oil. As he told his Cabinet on July 18, an embargo meant war, for that would force oil-starved Japan to seize the oil fields of the Dutch East Indies.(oil and gas are used widely in modern life. Oil fuels the cars, trucks and planes that underpin modern economies and lifestyles. ... Nearly all pesticides and many fertilisers are made from oil or oil byproducts. Gas provides electricity and is also used for cooking, heating houses and buildings, and heating water.)

c) he felt the constitution clearly gave states this right.