The United States is highly dependent on foreign oil. Well over half of the oil and petroleum products consumed in America--approximately 12 million barrels per day, or more than 600 gallons for every man, woman, and child each year--now come from abroad. And the U.S. government projects that the level of imports will only continue to rise, reaching between 16 and 21 million barrels per day by 2025. What precisely are the costs of U.S...