Lets not bicker about the specific problem. Does it really matter if it is global warming; pollution; destruction of the eco-system... The end result is the same, how you get there is irrelevant. Besides, those are simply symptoms of the real problem -- The world has too many people combined with the tragedy of the commons!
As far as I can tell, the best/only current solution to the worlds environmental problems is to release a bio-weapon that kills off about 90+% of the worlds human population and if necessary (The human population starts becoming a problem again) repeat process. We need to kill-off enough people that our impact on the commons (The earth) is negligable. At that point, assuming we aren't too late, nature will recover.
Hey, what does it matter, we as a human race are trying to destroy the worlds habitability anyway. Our default way, of denial or to wait and hope that technology will eventually solve our problems for us, just takes a lot longer and leaves the earth with much less ability to recover (Less bio-diversity). As long as we are in denial or waiting for some random event to occur then we are not taking responsibility for our actions so we can't do anything substantial to change those actions for a better result.
I am absolutely positive that the Bush administration would feel good about censoring me and my thoughts on the issue. Matter of fact, I can't think of an administration (any where in the world) that wouldn't. It just isn't politically correct.
Now what is the big problem with the Bush administration censoring its workers? They aren't any different than others that want to promote their ideas and suppress the contrary. Can you think of a company that would take kindly to its employees bad mothing the companies products or policies? The anology is no different here.
It is not the governments role to protect their citizens rights but rather it is the peoples responsibility. In the USA, we choose those that represent us. If we choose poorly, then we get what we deserve. We choose Bush. We choose our Senators, and Representatives. We choose our Governors, State representatives; We choose our city officials. By our choices, we get the ethics, values, opinions, policies, laws, ... Everything that our government is and represents directly and indirectly are caused by us, the citizens.
You don't like it, then make better choices. Get involved in the process. Express yourself to others and convince them that that your views are correct and so that they vote the way you do. Be happy, at least here we have choosen to allow most everyone to partisipate.