An oil shortage that may be real, predicted or caused by speculation. A sudden shortfall in supply versus demand causes oil prices to soar and triggers significant economic consequences on an international scale. There have been three oil crises in recent history. The first occurred in 1973 when Arab countries imposed an oil embargo on Israel’s supporters during the Yom Kippur War. The second arose in 1979 because of the Iran Revolution, followed by the Iran-Iraq War due to the attacks by Iraq. The third, in 2008, was caused by intense speculation.