In which I regurgitate opinions, and encourage some reading.
Quotes from Merchants of Doubt, by Naome Oreskes & Erik M. Conway:
On peddling false information: "Magical thinking still informs the position of many who oppose environmental regulation. As recently as 2007, the George Marshall Institute continued to insist that the damages associated with acid rain were always 'largely hypothetical,' and that'further scientific investigation revealed that most of them were not in fact occurring.' The Institute cited no studies to support this extraordinary claim."
On political motivation for anti-science mentality: "Some environmentalists no doubt are Socialists, but in our experience few climate scientists are. Moreover, even if all environmentalists were socialists, it does not follow that global warming is a myth."
On global warming: "Imagine a gigantic banquet. Hundreds of millions of people come to eat. They eat and drink to their hearts' content...Then, one day, a man arrives, wearing a white dinner jacket. He says he is holding the bill. Not surprisingly, the diners are in shock. Some begin to deny that this is their bill. Others deny that there even is a bill. Still others deny that they partook of the meal. One diner suggests that the man is not really a waiter, but only trying to get attention for himself or to raise money for his own projects. Finally, the group concludes that if they simply ignore the waiter, he will go away."