The implication of your post, Martin, is that democracy - understood as the consent of the governed - cannot be absolute.
I agree with this implication, and if it wasn't made - then I'd like to draw it out and argue the point by way of example.
In the United States, Lincoln and Douglas had a famous debate about slavery and democracy. The country was expanding - more and more people were moving west, and new Territories were being formed which eventually were getting so populated as to qualify for state-hood.
The big question of the day was: Should Slavery be allowed to exist in the terriroties, and should new states being admited into the Union be compelled to make slavery illegal or not?
Douglas argued that democracy should decide. He argued that some states, where people - for their own reasons - did not like Slavery, should be allowed to vote slavery illegal.
Other states could make it legal.
In all, Douglas argued, let democracy decide.
Lincoln made the argument that slavery was immoral, and that it could not be a decision left up to the majority. It could not be "voted on."
This, said Lincoln, was because the right to vote on government policy resulted from the idea that all humans were created equal - so, the argument went - since human equality gives everyone an equal vote - you cannot hold a vote on the question "is everyone equal?" or "should everyone have an equal vote?" -- that was essentially what Douglas was proposing when he said democracy should decide for or against slavery - to hold a voite saying "do you think all people are equal or not?"
This is contradictory with the principle of democracy.
The same can be said for any question of moral principle.
For instance - we cannot hold a vote on whether or not murder is ok.
We cannot hold a vote on whether or no punching people with red hair is ok.
We cannot hold a vote on whether or not people weighing between 89 and 92 kilos should be forbidden to speak.
No vote can ever be held on a question that presumes the winners of the vote will violate the natural rights of the loosers.
Yet in our day and age - the majority of democratic votes are always held this way. Political parties cater to constituencies, promising tax credits to some, welfare to some, special benefits to some - always at the expence of others.
The argument is then put forth that this "expense to others" is "fair" (for instance that the rich must pay more taxes, or that pickle growers can pay 7% VAT while toy sellers must pay 22% VAT because pickles are more "essential" than toys - but not as essential as - oh say - bread - which is taxed at 3% VAT- and none of these, apparently, are as "essential" as...say...used toys - which are taxed at 0% VAT.
In short - most of the West has gone from limited representative government to full blown demoracy - where the majority DOES decide who is a slave and who is free, who can take from others and who should be the beneficiary of this taking.
This is, in my view, tyranny of the majority - it is no different from a Dictator like Hitler or Stalin; only that this particular dictator is a faceless majority working through its' elected representatives.
But Lincoln's original point still remains: democracy - the idea that all people have an equal vote, is only true and just because all people are created equal in their natural rights. Once democracy starts voting on who has more or less rights, who is more or less equal, then it becomes the rule of a mob.
This is why I believe that environmental questions, like the majority of issues that cannot be strictly constructed as universally moral, should not even come under political activity.
The government should not have the right to "do something" about the environment just because 50.01% of the people say it should.
Some people argue that global warming and other environmental dangers are universal -that they are a threat to human existence - and they paint the picture that if government doesn't act, independent of whether people want it to or not - then we will all suffer horrible consequences.
Funny, of course, that the same rationale is used to justify the loss of civil liberties in the war on a handful of people with box cutters, lighters and home made explosives (the "war on terrorism") - who, it is said, are no less a threat than the combined forces of Hitler, Tojo, Genghis Khan, and Megatron's Decepticons riding around on Unicron....
Various interest groups all try to push their particular "scare of the hour" to the fore-front of the political agenda - and the only thing they can all agree upon is that all "scary agendas" ought to be taken into account - the idea is that if you agree to government funding of my scary agenda, I'll agree to government funding of yours - and we'll not waste time and resources fighting one another; except maybe some petty back and forth when it comes time to divy up the annual budget.
If somehow someone could prove, as Lincoln did with Slavery, that protecting the environment was a matter of universal morality and that it is not open to a vote - then clearly there would be a duty to protect the environment and the government would have to do it.
But the argument against slavery is easy - all individuals have rights: no one can be held as a slave - people who hold others as slaves are tyrants. The government must protect our lives and liberties from those who would make us - or others - slaves. Slavery is and should be illegal. If someone forcibly holds another person against their will (enslaves them) - we call it kidnapping.
The argument for environmental activism is...not so easy.... for starters - there is no scientific proof that global warming exists; no matter how loud some may shout about it; it is an open question.
Secondly; even if we accept that it exists - I highly doubt that the most logical way of combating it is returning mankind to the stoneage by hampering economic growth.
Economic growth provides the capital resources which are necessary for technology to progress - for instance - for technology to progress beyond the immediate consumption of oil towards the use of another, less scarce resource.
The resolution to the problem can come about by promoting economic growth; that is living people free and alone to do as they please, and by promoting private property.
Take for instance endangered species - is it any wonder that the vast majority of endangered species live in the "wild" - namely in areas of the Earth that are not owned, or are "public domain?"
This may sound silly at first - but please consider - why are chickens and cows NOT endangered species?
Lord knows they are slaughtered round the clock, year after year - yet there never seems to be a threat of KFC not having anything to cook.
Why is that?
Largely because farm animals are private property - and it is in the interst of the farmers who live off of the sale of poultry and other meats to take care that their livestock breed. Ergo; the market facilitates the existence of these species.
Other species which are not owned; but which "exist freely" on "no man's land" are not so well cared for.
We can, of course, declare that all animals have the right to life and that humans ought not hunt and eat them, let alone hunt them for sport.
But then, I would demand that animals respect our right to life as well - and if a tiger should happen to eat a poor tourist - I would like to know how I can go about prosecuting that tiger in Tiger-Land? I would like to know where the Tiger is a citizen, under what laws he acts, and how would it be possible to create - say - mutual extradition treatises between the EU and Tiger-Land?
Naturally - none of this would be possible because tigers and other animals are not people: they are not rational beings, not even potentially so - and therefore they do not have the same rights as humans. They can eat us if they are so inclined - and while we can be mad at a tiger for eating us, we ought not be angry in a personal way - the tiger was simply acting out of instinct - there is no "moral blame" here.
So - the short end of the stick is that either, if Martin is right, we admit that democracy is a failure and we need dictators who are enlightened by modern science and know that - say - a law should be passed forbidding driving on Sunday and Thursday else the sky fall out due to global warming...
or..
To just leave people alone.
Any middle ground is sure to become muddle ground.
My 19 cents on the issue
Pete