Domestic US oil production is in decline. A growing majority of oil supply to the US now comes from foreign sources. This creates a situation of energy vulnerability or ‘in-security''. This dynamic is a challenge to the US on two folds; politically because the US is a world leader, and economically because the US has one of the largest global economies. The book explores the significance and potential contribution deepwater oil supply from the Gulf of Mexico can make in providing energy security to the US. With so much current debate on the pros and cons of deepwater oil exploration in US offshore territories, this study will seek to understand and quantify the significance of its development for domestic US energy supplies in the near term. The book demonstrates how significant is deepwater oil supply from the Gulf of Mexico to domestic energy in the US. How key is it for the US government and the future domestic energy investment. Answers will be provided based on three different scenarios; these are law, medium and high cases. Our results reveal that deepwater oil drilling in the Gulf of Mexico provides energy security to the US on the short to medium term.