In 1973, oil dependence became visible in lines outside gas stations.
During the Arab-Israeli war, Arab oil exporters restricted shipments to the United States and other countries that supported Israel.
Prices rose sharply because the embargo hit an economy already dependent on imported oil.
Washington's response included conservation measures such as the 55 mph speed limit and later fuel-economy standards for new cars.
The shock did not create energy policy by itself. It made efficiency feel like security, not just thrift.