Why can't the US use its own oil?

US does use its own oil and is the world's largest oil producer at about 12 to 13 million barrels per day, but it cannot meet all demand with domestic oil alone for several reasons. US consumes about 20 million barrels per day of petroleum products, so production is less than consumption, requiring imports to fill the gap, though US also exports oil, making it net importer of crude but net exporter of total petroleum. Another major reason is refinery mismatch: US shale oil from Texas and North Dakota is light sweet crude, but many large US refineries, especially on Gulf Coast, were built decades ago to process heavy sour crude from Canada, Mexico, and Venezuela, which yields more diesel and is more profitable for those complex refineries. So they import heavy crude and export light crude. Oil is also global commodity, companies sell to highest bidder worldwide. Pipeline and infrastructure constraints limit moving domestic oil to all refineries. To be fully self-sufficient, US would need to reconfigure refineries, reduce consumption, and stop exports, which would be costly. So US does use its own oil, about 60 to 70 percent of crude refined is domestic, but cannot supply 100 percent due to consumption volume and refinery design.

US does use its own oil, it is largest oil producer producing about 12 to 13 million barrels per day, and much of that is refined and used domestically, but it cannot meet all demand with own oil alone and refinery mismatch causes need for imports. US consumes about 20 million barrels per day of petroleum products, so even as top producer, it produces less than it consumes, needing imports to fill gap, though it also exports oil. Another reason is type mismatch, US shale oil is light sweet crude, but many US refineries, especially Gulf Coast, were built decades ago to process heavy sour crude from Canada, Mexico, and Venezuela, as light shale is relatively new, so they need heavy crude for efficient operation and to make diesel and other products, so US exports light oil and imports heavy oil. Also oil is global commodity traded on global market, companies sell to highest bidder, so US oil may be exported if price better abroad. Infrastructure and pipeline constraints also limit moving domestic oil to all refineries. So US does use its own oil, about 60 to 70 percent of crude refined is domestic, but cannot be fully self-sufficient without changing refineries, reducing consumption, and stopping exports, which would raise costs.