Initially describing himself as a socialist, Hitchens began his break from the established political left after what he called the "tepid reaction" of the Western left to the Rushdie Affair. The September 11 attacks "exhilarated" him, strengthening his internationalist embrace of an interventionist foreign policy, and his criticism of what he called "fascism with an Islamic face." His numerous editorials in support of the Iraq War caused some to label him a neoconservative, although Hitchens insisted he was not "a conservative of any kind", and his friend Ian McEwan described him as representing the anti-totalitarian left.
A noted critic of religion and a self-described anti-theist he said that a person "could be an atheist and wish that belief in God were correct", but that "an anti-theist a term I'm trying to get into circulation, is someone who is relieved that there's no evidence for such an assertion." According to Hitchens, the concept of a god or a supreme being is a totalitarian belief that destroys individual freedom; and, that free expression and scientific discovery should replace religion as a means of teaching ethics and defining human civilization. His anti-religion polemic, God Is Not Great, sold over 500,000 copies.
Hitchens died on 15 December 2011, from complications arising from oesophageal cancer, a disease that he acknowledged was likely due to his lifelong predilection for heavy smoking and drinking. His death prompted tributes and eulogies from a range of public figures, including Tony Blair, Richard Dawkins, Sam Harris, Lawrence Krauss, Martin Amis, James Fenton, and Stephen Fry.
Hitchens often spoke out against the Abrahamic religions, or what he called "the three great monotheisms" (Judaism, Christianity and Islam). When asked by readers of The Independent (London) what he considered to be the "axis of evil," Hitchens replied "Christianity, Judaism, Islam - the three leading monotheisms." In his book, God Is Not Great, Hitchens expanded his criticism to include all religions, including those rarely criticized by Western secularists such as Hinduism and neo-paganism. His book had mixed reactions, from praise in The New York Times for his "logical flourishes and conundrums" to accusations of "intellectual and moral shabbiness" in the Financial Times. God Is Not Great was nominated for a National Book Award on 10 October 2007.
In February 2010, he was named to the Freedom From Religion Foundation's Honorary Board of distinguished achievers.
Former British Prime Minister Tony Blair said, "Christopher Hitchens was a complete one-off, an amazing mixture of writer, journalist, polemicist, and unique character. He was fearless in the pursuit of truth and any cause in which he believed. And there was no belief he held that he did not advocate with passion, commitment, and brilliance. He was an extraordinary, compelling and colorful human being whom it was a privilege to know."
Richard Dawkins, British evolutionary biologist at the University of Oxford and a friend of Hitchens, said, "I think he was one of the greatest orators of all time. He was a polymath, a wit, immensely knowledgeable, and a valiant fighter against all tyrants including imaginary supernatural ones."
Sam Harris, American writer and neuroscientist, wrote, "I have been privileged to witness the gratitude that so many people feel for Hitch’s life and work—for, wherever I speak, I meet his fans. On my last book tour, those who attended my lectures could not contain their delight at the mere mention of his name—and many of them came up to get their books signed primarily to request that I pass along their best wishes to him. It was wonderful to see how much Hitch was loved and admired—and to be able to share this with him before the end. I will miss you, brother.