A school of political thought in the USA. Neoconservatism first emerged in the 1970s and is distinguished from other strands of conservatism by its approach to foreign policy, which holds that security is best attained by using US power to spread freedom and democracy, if necessary by force and without international cooperation. Many early neoconservatives were former liberals converted to conservatism by the perceived failures of liberal and multilateral foreign policies: as Irving Kristol (1920–2009), a prominent neoconservative thinker, famously phrased it, a neoconservative is “a liberal mugged by reality”. Neoconservatives were strong opponents of communism and supporters of the Cold War and have exercised some influence during the administration of all Republican presidents since Ronald Reagan. Their prominence grew after September 11, 2001, when their views coincided with the perceived need for an assertive foreign policy to combat the terrorist threat to the USA. In particular, the invasion of Iraq (2003) and the subsequent attempt to establish a democratic regime there chimed closely with neoconservative ideals (see iraq war). Neoconservatism has been criticized on several grounds, including the charge that its definitions of “freedom” and “democracy” are essentially American and so cannot be imposed successfully on other countries and cultures.