I believe the United States can meet its transportation needs by producing all the oil it requires domestically. This would require some changes in law and some adaptation in our refineries so they can process fracked oil. By law, we would need to keep the price of gasoline high enough, about three to four dollars per gallon, to ensure that American producers can make a profit; and we would need to modify existing refineries so they can handle the types of oil we produce. It is estimated that, at current usage levels, the United States has roughly 30 to 50 years of economically recoverable shale oil available, which would hopefully be enough time to convert to electricity‑based transportation. To make this work, we would also have to prohibit foreign oil, especially cheap foreign oil that undercuts American producers.