Oil
An article by Josef Braml in the Washington Quarterly has these insights
Since the 1950s, U.S. energy consumption, mainly driven by the transportation sector and fed by oil, has almost tripled....
Although the United States has managed to boost oil production from 5.9 million barrels per day in 1950 to 7.8 million barrels per day in 2005, this is not sufficient con¬sidering the daily need of 20.7 million barrels, two-thirds of which is consumed by the transportation sector.
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Due to higher oil prices, energy imports add¬ed about $70 billion to the U.S. trade deficit in 2005 and $50 billion in 2006.25 They currently account for roughly one-third of the current trade imbalance.
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Oil consumption accounts for about 40 percent of energy-related carbon di¬oxide emissions, which cause pollution, human health problems, and climate change.