"The Obama Administration views Iran as a major threat to U.S. national security interests, a perception generated not only by Iran's nuclear program but also by its military assistance to armed groups in Iraq and Afghanistan, to the Palestinian group Hamas, and to Lebanese Hezbollah. Particularly in its first year, the Obama Administration altered the previous U.S. approach by offering Iran's leaders consistent and sustained engagement with the potential for closer integration with and acceptance by the West. To try to convince Iranian leaders of peaceful U.S. intent and respect for Iran's history and stature in the region, the Obama Administration downplayed any discussion of potential U.S. military action against Iranian nuclear facilities or efforts to try to change Iran's regime. It held to this position even at the height of the protests by the domestic opposition 'Green movement' that took place for the six months following Iran's June 12, 2009, presidential election but largely ceased in 2010."
CRS Report for Congress, RL32048
U.S. Department of State, Foreign Press Centers: http://fpc.state.gov/