The event that severely weakened the U.S. economy in 1973 was the Oil Crisis.
The Oil Crisis of 1973 began on October 16, 1973, following the decision of the Organization of Arab Oil Exporting Countries and Iran of not to export more oil to the countries that had supported Israel during the Yom Kippur war, which faced Israel against Syria and Egypt. This measure included the United States and its Western European allies.
The increase in price, together with the heavy dependence of the industrialized world on oil, caused a strong inflationary effect and a reduction in the economic activity of the affected countries. These countries responded with a series of permanent measures to curb their external dependence.