To quote the article:
Whatever they are denying, denial movements have much in common with one another, not least the use of similar tactics (see "How to be a denialist"). All set themselves up as courageous underdogs fighting a corrupt elite engaged in a conspiracy to suppress the truth or foist a malicious lie on ordinary people. This conspiracy is usually claimed to be promoting a sinister agenda: the nanny state, takeover of the world economy, government power over individuals, financial gain, atheism.
Similarly, global warming, evolution and the link between tobacco and cancer must be taken on trust, usually on the word of scientists, doctors and other technical experts who many non-scientists see as arrogant and alien.
Many people see this as a threat to important aspects of their lives. In Texas last year, a member of a state committee who was trying to get creationism added to school science standards almost said as much when he proclaimed "somebody's got to stand up to experts".It is this sense of loss of control that really matters. In such situations, many people prefer to reject expert evidence in favour of alternative explanations that promise to hand control back to them, even if those explanations are not supported by evidence.