Based on information provided by the US Department of Energy, 40 percent of the United States' energy requirements are being met through the use various petroleum products. This is a cause for concern among many people who think that the country should be implementing measures to slowly shift towards sustainable sources of oil.
About 40 percent of the country's oil is sourced from local oil fields -- like those located in Texas, Alaska and California. A part of these oil resources are actually sold to other countries like Japan. The remaining 60 percent of the country's oil requirements are taken from foreign sources. The US actually has a very wide oil interest placed all over the world. It imports oil and other petroleum products from practically every continent. This level of diversity in establishing the US oil supply is crucial in allowing the country to manufacture a diverse range of petroleum products that use crude oil in various chemical configurations.
Some of the countries that contribute largely to the US' oil requirements include Canada, Colombia, Saudi Arabia, Nigeria, Angola and Iraq. The US also gets oil from Norway, the United Kingdom, Kuwait, Venezuela, Algeria and Equatorial Guinea. On the other hand, many other countries export refined oil product to the United States to supplement the products that are being manufactured in local refineries in the country. The large diversity of sources for the US oil supply ensures that it will be difficult to cut off the supply of oil to the country completely.