Over the last six years, net oil imports have fallen by 33% to average 8.4 million barrels per day (Mb/d) in 2011. This represents 45% of domestic consumption, down from 60% in 2005. Oil is a critical resource for the U.S. economy, but despite policy makers' longstanding concern, U.S. oil imports had generally increased for decades until peaking in 2005. Since then, the economic downturn and higher oil prices were a drag on oil consumption, while price-driven private investment and policy helped increase domestic supply of oil and oil alternatives. Net imports are gross imports minus exports. The decline in net imports has manifested itself as a decrease in gross imports and an increase in exports of petroleum products. Gross U.S. imports of crude oil and petroleum products averaged 11.4 Mb/d in 2011, down 17% since 2005. More than a third of gross imports came from Canada and Mexico in 2011. About 40% came from members of the Organization for the Petroleum Exporting Countries (OPEC), mostly from OPEC members outside the Persian Gulf. Regionally, the largest share of U.S. imports come into the Gulf Coast region, which holds about half of U.S. refining capacity and sends petroleum products to other parts of the country and abroad. All regions of the country import more crude than refined products except for the East Coast, where petroleum products imports may rise further due to refinery closures. U.S. oil exports, made up almost entirely of petroleum products, averaged 2.9 Mb/d in 2011. This is up from export of 1.2 Mb/d in 2005, led by growing export of distillates (diesel and related fuels) and gasoline. More than 60% of U.S. exports went to countries in the Western Hemisphere, particularly to countries such as Mexico and Canada from which the U.S. imports crude oil. Exports occur largely as a result of commercial decisions by oil market participants which reflect current oil market conditions as well as past investment in refining. As a result, net oil imports fell from a peak of 12.5 Mb/d in 2005 to 8.4 Mb/d in 2011, their lowest level since 1995. A consensus is generally emerging among energy analysts that U.S. oil imports may be past their peak, reached in 2005. Imports as a share of consumption are expected to fall further, to less than 40% after 2020 driven by tighter fuel economy standards and increased domestic supply. Despite the decline in net import volumes, the cost of net imports has increased due to rising oil prices. The aggregate national cost of oil imports is a function of the volume of oil imported and the price of that oil. The United States spent about $327 billion on net oil imports in 2011. Being a net importer of a particular good is not necessarily negative for an economy, but greater national oil import dependence can amplify the negative economic impacts of oil price increases. Oil import and export developments pose a host of policy issues. Concerns about import dependence continue to generate interest in policy options to directly discourage imports or to reduce the need for imports by increasing domestic supply and decreasing demand. Rising exports at a time of rising prices has led to calls for policies to restrict such trade. The debate around the Keystone XL pipeline involves concerns about imports, exports, and the environment. The rising cost for fuels has led to calls for release of the Strategic Petroleum Reserve, meant to provide a short term policy option in case of supply disruptions. Policy options may entail various economic, fiscal, and environmental trade-offs.

Some officials of the Islamic Republic of Iran have recently renewed threats to close or exercise control over the Strait of Hormuz. Iran's threats appear to have been prompted by the likely imposition of new multilateral sanctions targeting Iran's economic lifeline-the export of oil and other energy products. In the past, Iranian leaders have made similar threats and comments when the country's oil exports have been threatened. However, as in the past, the prospect of a major disruption of maritime traffic in the Strait risks damaging Iranian interests. U.S. and allied military capabilities in the region remain formidable. This makes a prolonged outright closure of the Strait appear unlikely. Nevertheless, such threats can and do raise tensions in global energy markets and leave the United States and other global oil consumers to consider the risks of another potential conflict in the Middle East. This report explains Iranian threats to the Strait of Hormuz, and analyzes the implications of some scenarios for potential U.S. or international conflict with Iran. These scenarios include: (1) Outright Closure. An outright closure of the Strait of Hormuz, a major artery of the global oil market, would be an unprecedented disruption of global oil supply and contribute to higher global oil prices. However, at present, this appears to be a low probability event. Were this to occur, it is not likely to be prolonged. It would likely trigger a military response from the United States and others, which could reach beyond simply reestablishing Strait transit. Iran would also alienate countries that currently oppose broader oil sanctions. Iran could become more likely to actually pursue this if few or no countries were willing to import its oil. (2) Harassment and/or Infrastructure Damage. Iran could harass tanker traffic through the Strait through a range of measures without necessarily shutting down all traffic. This took place during the Iran-Iraq war in the 1980s. Also, critical energy production and export infrastructure could be damaged as a result of military action by Iran, the United States, or other actors. Harassment or infrastructure damage could contribute to lower exports of oil from the Persian Gulf, greater uncertainty around oil supply, higher shipping costs, and consequently higher oil prices. However, harassment also runs the risk of triggering a military response and alienating Iran's remaining oil customers. (3) Continued Threats. Iranian officials could continue to make threatening statements without taking action. This could still raise energy market tensions and contribute to higher oil prices, though only to the degree that oil market participants take such threats seriously. If an oil disruption does occur, the United States has the option of temporarily offsetting its effects through the release of oil from the Strategic Petroleum Reserve. Such action could be coordinated with other countries that hold strategic reserves, as was done with other members of the International Energy Agency after the disruption of Libyan crude supplies in 2011. Iran's threats suggest to many experts that international and multilateral sanctions-and the prospect of additional sanctions-have begun to affect its political and strategic calculations. The threats have been coupled with a publicly announced agreement by Iran to resume talks with six countries on measures that would assure the international community that Iran's nuclear program is used for purely peaceful purposes. Some experts believe that the pressure on Iran's economy, and its agreement to renewed talks, provide the best opportunity in at least two years to reach agreement with Iran on curbing its nuclear program.

In 2008, Canadian pipeline company TransCanada filed an application with the U.S. Department of State to build the Keystone XL pipeline, which would transport crude oil from the oil sands region of Alberta, Canada, to refineries on the U.S. Gulf Coast. Keystone XL would ultimately have the capacity to transport 830,000 barrels per day, delivering crude oil to the market hub at Cushing, OK, and further to points in Texas. TransCanada plans to build a pipeline spur so that oil from the Bakken formation in Montana and North Dakota can also be carried on Keystone XL. As a facility connecting the United States with a foreign country, the pipeline requires a Presidential Permit from the State Department. In evaluating such a permit application, the department must determine whether it is in the "national interest," considering the project's potential effects on the environment, economy, energy security, foreign policy, and other factors. Environmental impacts are considered pursuant to the National Environmental Policy Act, and documented by the State Department in an Environmental Impact Statement (EIS). The final EIS was released for the Keystone XL pipeline permit application in August 2011, after which a 90-day public review period began to make the national interest determination. During that time the State Department determined that more information was needed to consider an alternative pipeline route avoiding the environmentally sensitive Sand Hills region of Nebraska, an extensive sand dune formation with highly porous soil and a shallow depth to groundwater recharging the Ogallala aquifer. The Temporary Payroll Tax Cut Continuation Act of 2011 (P.L. 112-78) required the Secretary of State to approve or deny the project within 60 days. On January 18, 2012, the State Department, with the President's consent, denied the Keystone XL permit, citing insufficient time under this deadline to properly assess the reconfigured project. Subsequently, TransCanada announced that it would proceed with development of the pipeline segment connecting Cushing, OK, to the Gulf Coast as a stand-alone project not requiring a Presidential Permit-a decision supported by the Obama administration. In April 2012, TransCanada submitted to Nebraska proposed pipeline routes avoiding the Sand Hills. Subsequently, on May 4, 2012, TransCanada submitted a new application for a Presidential Permit that includes proposed new routes through Nebraska. With the new permit application, the NEPA compliance process begins anew, although it may draw from relevant existing analysis and documentation prepared for the August 2011 final EIS. In the wake of the State Department's denial of the Presidential Permit, Congress has debated legislative options addressing the Keystone XL pipeline. The Surface Transportation Extension Act of 2012, Part II (H.R. 4348) and the North American Energy Access Act (H.R. 3548) would transfer the permitting authority for the Keystone XL pipeline project to the Federal Energy Regulatory Commission, requiring FERC to issue a permit within 30 days of enactment. The Keystone For a Secure Tomorrow Act (H.R. 3811), the Grow America Act of 2012 (S. 2199), S. 2041 (a bill to approve the Keystone XL pipeline), the EXPAND Act (H.R. 4301), and the Energizing America through Employment Act (H.R. 4000) would immediately approve the original permit application filed by TransCanada.