In the wake of the September 11 terrorist attacks, the United States embarked on a major anti-terrorism campaign abroad and at home. International elements included the war in Afghanistan, to root out al-Qaeda and the Taliban; increased law enforcement cooperation; and new measures to monitor the movement of goods and people across borders. At home the Department of Justice, its Federal Bureau of Investigation, and later the new Department of Homeland Security, led domestic efforts to find people connected with the September 11 attacks and to prevent future terrorist activity in the US.