In 1973 OPEC countries imposed an oil embargo to retaliate for US support of Israel during the Yom Kippur War. Drivers endured soaring gasoline prices, blocks-long lines, hours wasted waiting to refuel vehicles, and restrictions on which days they could buy fuel. America was vulnerable to those blackmail sanctions because we imported "too much" oil--though it was just 30% of our crude.
The fracking revolution (horizontal drilling and hydraulic fracturing) and other factors changed that dramatically. The United States now produces more crude oil than at any time since 1970.