If one is not allowed to mention or entertain an idea without career repercussions, it harms the scientific process. Similarity to the treatment of climate change "deniers" comes to mind.
The merit for the cause of climate change should be based on evidence, not by keeping opposing views off the table by threatening the careers of those who want to explore research other ideas.
Sometimes a new idea needs to spend it's time out in the wilderness before proving itself. That's because real science progresses based on proof, not just one or two data points that may or may not be significant. The fact is there were scientists that supported the theory and they didn't all get sacked, and nor did Wegener.
The real problem is that sometimes all we have are a few data points. That's when opinion and fact can get blurred, and geology was in that situation before the 50s. Nobody could prove continental drift and nobody could disprove it. That doesn't mean that those who doubted it were stupid, in fact several of the scientists resonsible for producing the most compelling evidence for the theory were initialy sceptics. That didn't stop them doing good science and following the evidence.
Its far too easy to look at an episode in the hitory of science like this and draw a bright triumphalist line between those who were right and those who were in the end proven wrong.
If you would read history, you would actually find that AGW had similar story as Wegener theory, if anything. Until Keeling and Plass came, nobody took the Arrhenius' and Chamberlin's idea seriously. And there was even experimental evidence from Calendar.
And the same goes for Milankovitch cycles, which are one of the most important pieces of evidence for AGW.
Even scientists such as Freeman Dyson and Hendrik Tennekes had their reputations smeared for daring to express skepticism over the most dire claims of catastrophic AGW proponents. Dyson didn't even claim that the Earth wasn't warming, he simply criticized the then strong faith in the predictions of GCMs, and the popularization of extreme catastrophic claims such as a 20 foot rise in global sea levels this century. Physics Nobel Laureate Ivar Giaever quit the American Physical Society, saying “In the APS it is ok to discuss whether the mass of the proton changes over time and how a multi-universe behaves, but the evidence of global warming is incontrovertible?”
The Climate Gate scandal showed irrefutably that prominent scientists in the climate research community conspired to spike the publication of dissenting scientists.
Expressing skepticism regarding catastrophic AGW has unquestionably been a 21st shibboleth. Even skeptics of the Big Bang aren't branded as "Deniers" with editorials from prominent policy advisors (James Hansen) calling for charging them with "high crimes against humanity and nature."
For the record, I am not a "Denier," so please no scarlett letter "D."
Catastrophic claims do no good, that's true. But frivolous skepticism (without a good counter-theory) has policy implications (continuing business as usual, which is unsustainable). The scientists opposing AGW are not being mass criticized for their scientific opinion (because they don't have any), but for the policies they give support to.
I also disagree with your interpretation of climate gate, but let's leave that.
What are they hiding? It turned out, nothing!
http://en.wikipedia.org/wiki/Alfred_Wegener
Just a small number of scientist were very sure, namely Wegener's father in law and mentor Köppen and also Milutin Milankovitch, whose own climate work was also mostly recognized and rightly understood only after his death. Milankovitch wrote about the continental drift in his books that popularised science in the thirties.
Can this be extended to politics as well ? What about the recent Uber executive mentioning that they thought about investigating the private lives of journalists to give them a taste about their own medicine ? If they did not actually do it, is it OK for them to mention it ?
Is it because it is done as retaliation? If uber had started to dig up dirt first would that be ok?
Or is it because only media is allowed to dig up dirt? Would it be ok for uber to pay another newspaper to look into the first one?