A 2016 study argued that oil wars were largely a myth. It argued that proponents of oil wars underestimate the ability to seize and exploit foreign oil fields, and thus exaggerate the value of oil wars. The study examined four cases commonly described as oil wars (Japan's attack on the Dutch East Indies in World War II, Iraq's invasion of Kuwait, the Iran-Iraq War, and the Chaco War between Bolivia and Paraguay), finding that control of additional oil resources was not the main cause of aggression in the conflicts.