A few years back, Michael Crichton published State of Fear, which was far less a novel than an inept position paper. Possessed of a tortured and unbelievable plot, wooden characters, and many pages of highly selective scientific data (replete with charts and footnotes) and pseudo-scientific exposition, the book was only worth reading for insight into the minds of climate contrarians (or deniers depending on your preferred terminology). The book had two essential premises: 1) those who support the idea of anthropogenic global warming do so for reasons of personal, professional and organizational economic gain and aggrandizement, and that these people are therefore willing to go to any lengths, including the wholesale murder of entire populations through manufactured environmental catastrophes, to protect their interests and promote acceptance of anthropogenic global warming by the public and politicians; and 2) governments (that is the "state" in the title) require the maintenance of fear in order to exert control in the population, and in the absence of old enemies (communism), government has turned to an environmental bogeyman to exert control.
Let's deal with premise number two first. Governments have used fear as a mechanism of control, especially when bent on limiting civil liberties and political opposition, and expanding the power of office holders. This describes the Bush administration. However, the Bush administration spent seven of its eight years denying global warming, and doing its best to silence scientists in NASA, NOAA, the EPA and CDC and stifle data supportive of the anthropogenic global warming. The Bush administration favorite bogeyman is "Islamic terrorism" not global warming. Which leads us to premise number one. Certainly millions of dollars of research money, from both government and industry is at stake for scientists, their departments and their institutions. But under the Bush administration, large-scale government monies were not flowing to scientists studying climate change, and the industries (coal, electricity generation, oil, etc.) with the most money to spend on climate research are largely those whose stake is in undermining the anthropogenic global warming hypothesis.
Why spend so much time talking about a bad novel? Because those two key premises are widely believed by many people. Over and over, in blogs, in on-line discussions, on talk shows, on Fox News, and many other media outlets, the belief is expressed that those who support the idea of anthropogenic global warming are motivated by the exact same things -- greed and power -- that motivate those who oppose the idea.
Americans have become disenchanted with politics (many sociologists would call it alienation). Quite accurately, Americans are aware of the role of money in politics. They know that the pharmaceutical corporations spend millions in lobbying money and campaign contributions and public relations ads to insure that they will continue to make billions and billions in profits on drugs. They know that corporations like Halliburton and its subsidiaries have made millions in profits on no-bid contracts in Iraq while American soldiers and Iraqi civilians die -- sometimes as a direct result of the shoddy work done on those contracts, like the soldiers electrocuted by poor wiring jobs done by a Halliburton subsidiary. Americans also know that things that their government identifies as threats often turn out not to be supported by fact. Many Americans believe that Bush and Cheney knowingly lied about the presence of weapons of mass destruction in Iraq, whipping-up fear to support a war that had far more to do with shoring up the dollar and protecting access to oil supplies, than it ever had to do with terrorism and military threat. So it is not surprising that many Americans also look at claims about the dangers of global warming with distrust.
They have come to expect people to act politically only out of self-interest in amassing wealth and power, and to expect that fear-mongering will play a major role in promoting that self-interest. The idea that scientists might operate on different, more disinterested principles, requiring rigorous testing, verification and review is beyond the comprehension of most people. This is not to say that scientists are not human and that they care nothing at all for career advancement, salaries, or grants; of course they are and they do.
Individual scientists fake data and lie about their results. However, they are usually caught at it and disgraced, because the scientific endeavor as a whole has built into it many mechanisms for feedback, review, oversight, and correction based on empirical evidence.
Most Americans do not understand that science is a process and a social process at that. Our educational system is at fault in this. The only exposure of most people to science is reading a few dry textbooks that present a list of terms, facts and numbers to be memorized and accepted by fiat. The social process of science in which the results of each individual scientists study are reviewed by many others, and tested repeatedly by others in other settings, has built into it corrections that tend to weed out that which is cannot be replicated and supported.
Science is not infallible. Scientists do sometimes go down the wrong alley, but this is always corrected by other scientists. Climate change science has been around a lot longer than the general public has been aware of it - and contrary to some media claims has been focused on global warming not cooling. Long before it became climate change became a political issue, the scientific process of review pruned away most of the false leads and blind alleys. There is still a great deal of uncertainty on specific mechanisms, specific consequences, and the specific patterns and timetables through which the general trend of anthropogenic global warming will play out.
Politicians and the political process may "squelch dissent," but science uses a process of peer review to sort between that which has the greatest empirical support and that which fails the tests of reviews and replication. This means that some people don't get their papers and their research published. This is not sinister, its how the scientific process works. Sometimes this means that good ideas and groundbreaking research doesn't get published. But if there's validity in it, other people will pick it up and work on it, providing more data, more corraboration, until ultimately it will get recognized.