The discovery of a new oil field in North Dakota would have a profound effect on the United States. North Dakota is among the top five oil producing areas as of 2014.
Oil is mostly produced by the following areas of the United States (in order from most to least): Texas, Gulf of Mexico, North Dakota and California.
The discovery of a new oil field would affect the United States in both (North Dakota) state and federal economics by creating jobs and capitalizing off of sales of oil both domestically and to foreign countries.
As of 2017, the US importing of oil was at its lowest point since 1970. Top oil imports come from Canada, Saudi Arabia, Venezuela, Mexico, and Iraq (in order from most to least). The discovery of new oil fields would probably even further decrease the amount of oil imports, which in the case of war, it would be a good thing to have our own easily accessible supply.
