Divided again by war
After a rare, brief moment of national unity following the Sept. 11, 2001, terrorist attacks, the country again found itself deeply polarized as President George W. Bush, with the support of congressional Republicans and many Democrats, launched the 2003 invasion of Iraq to rid the country of alleged stockpiles of weapons of mass destruction. Early opposition to the war was led primarily by liberals.
While it took only days to topple the government of Saddam Hussein, a deadly insurgency soon emerged. As the death toll of Iraqi civilians and U.S. troops mounted in the years that followed, public opinion turned against the conflict, and some of the largest demonstrations since the Vietnam War were held in American cities. Despite growing dissatisfaction with his performance, Bush narrowly defeated Sen. John F. Kerry (D-Mass.) in the 2004 presidential election, during which the Iraq war and national security were central issues. The war in Iraq also played a major role in the 2008 Democratic primary campaign, in which then-Sen. Barack Obama (D-Ill.) positioned himself as an antiwar candidate, in contrast to then-Sen. Hillary Clinton (D-N.Y.), who voted to authorize military force against Iraq in 2002.