Christopher Hitchens (13 April 1949 – 15 December 2011) was a British-American author, polemicist, debater and journalist who in his youth took part in demonstrations against the Vietnam War, joined organisations such as the International Socialists while at university and began to identify as a socialist. However, after the 11 September attacks he no longer regarded himself as a socialist and his political thinking became largely dominated by the issue of defending civilization from terrorists and against the totalitarian regimes that protect them. Hitchens nonetheless continued to identify as a Marxist, endorsing the materialist conception of history, but believed that Karl Marx had underestimated the revolutionary nature of capitalism. He sympathized with libertarian ideals of limited state interference, but considered libertarianism not to be a viable system. In the 2000 U.S. presidential election, he supported the Green Party candidate Ralph Nader. After 9/11, Hitchens advocated the invasion of Iraq. In the 2004 election, he very slightly favored the incumbent Republican President George W. Bush or was neutral and in 2008 he favored the Democratic candidate Barack Obama.