The article discusses how U.S. foreign policy changed after the 9/11 attacks. It looks at how the events of 9/11 influenced America's approach to the world, especially under President George W. Bush and the impact of neo-conservatism. The article also examines how the use of military power shaped U.S. foreign policy post-9/11, including the invasion of Iraq. It concludes by evaluating Barack Obama's strategies on terrorism and foreign policy in general.