With concern in the West mounting over Iran's nuclear ambitions, some lawmakers and policy advocates are pushing for a fresh round of sanctions aimed at halting Tehran's uranium-enrichment program. In March 2009, President Barack Obama, like President George W. Bush and President Bill Clinton before him, renewed an executive order banning U.S. investment in Iran's energy sector. Talks involving Iran, the United States, and other world powers engaged in the diplomatic process over Iran's nuclear program are scheduled for October 1. Yet demands for a fourth round of UN Security Council sanctions continue to be seen as an important form of international leverage. "There is unanimity within the P-5+1 [the UN Security Council, plus Germany] in support of our two-track approach that involves engagement and pressure," U.S. Assistant Secretary of State Philip J. Crowley told journalists in September 2009. Some Iran analysts are urging Washington to act sooner (Bloomberg) to further toughen existing U.S. and international sanctions. Other analysts, including John Bolton, former U.S. ambassador to the UN, suggest only military force (WSJ) will prevent a nuclear-armed Iran.
The long list of U.S. economic and political sanctions against Iran has its root in the 1979 Tehran hostage crisis. On November 14, 1979, President Jimmy Carter declared an emergency and ordered a freeze on all Iranian assets "which are or become subject to the jurisdiction of the United States." The emergency order has been extended every year since, most recently by President Barack Obama in March 2009. Additional sanctions were imposed when, in January 1984, Iran was implicated in the bombing of the U.S. Marine base in Beirut, Lebanon. The United States added Iran to its list of countries that support terrorism...