Your argument explicitly mentions "anyone" and "political classes"; in no way does it single out scientists. It's a very general argument which, based on context, I assumed you were specializing to scientists.

If you wish to claim it is true for scientists, but not people in general, you'll need to explain what special features of scientists make the argument true for them.

In any case, there is direct benefit to climate scientists to exaggerate the dangers/probabilities of climate change: it raises the importance of their field and by extension themselves. Exaggerated fears of global warming benefit climate scientists, just as exaggerated fears of the next great depression benefited Nouriel Roubini.

I was responding to the vague claim that statists, who have an interest in increasing the power of the federal government, are exerting influence on climate scientists to fraudulently manufacture a rationale for a presumably wide-ranging and invasive intervention in the economy. My argument is that it's very hard to identify any sufficiently powerful group with any identifiably vested interest in fraudulent climate science other than the petroleum, automotive, and energy industries.

Actually, it's not the slightest bit hard:

> Consider the case of Phil Jones, the director of the CRU and the man at the heart of climategate. According to one of the documents hacked from his center, between 2000 and 2006 Mr. Jones was the recipient (or co-recipient) of some $19 million worth of research grants, a sixfold increase over what he'd been awarded in the 1990s.

Source: http://online.wsj.com/article/SB1000142405274870393940457456...

There is no rational way one can claim that dramatizing your findings doesn't increase your exposure and make you more likely to get grants, and there's no rational way to claim that scientists don't really, really want grants. There's also no reason to believe scientists/policy promoters aren't just as passionate about their goals as Exxon executives are about theirs.

And, no, scientists' chief goals are not the clear and unvarnished pursuit of truth. Scientists are people who want to be recognized for the amazing truths they've uncovered. If, after 30 years, you find that the evidence of your research does not support any significant insights into public policy, then a scientist, like any other person, will feel that their life has been wasted. Worse still is when the expectation has been set up, by 30 years of press and publicity, that their studies did matter and were of the most urgent importance. Losing that would be almost impossible to endure. And there's zero reason to believe scientists are able to endure this more than anyone else.

(It would be amazing if scientists had the ability to say "Hey, this path didn't lead anywhere, but I contributed to our understanding of the world by cutting off these possibilities". Sadly, scientists are human just like the rest of us. Science is the worst way to apprehend the world, except for all the others.)

Remember, no one is claiming that climate scientists are in a conspiracy to trick people into thinking there is global warming when they don't think there really is. That is a pure straw man by pro-AGW folks. What many people do feel is that numerous factors, including the natural vanity, zeal, and self-importance of the small community of climate scientists, are causing them to overstate their findings.

Fine, let's test that hypothesis: climate scientists overstate their findings. If climate scientists overstate their findings, we would expect them to, among other things, overestimate the rate of glacial melting. But in fact, most of the findings (the IPCC findings in particular) underestimate the rate of glacial melting. Hmm....

It's very hard to identify any sufficiently powerful group with any identifiable profit motive for fraudulent sex research either.

People sometimes push an agenda for irrational ideological reasons rather than simply profit.

Incidentally, bad sex research was fairly common. Homosexuality used to be classified as a disease, for example.