Because the working class movement is presently weak and disorganized. The task of activists is to help the movement revive. This means helping it fight against all the threats that capitalist life poses to the people.
> Particulate pollution is a deadly serious matter, far more serious than
>carbon emissions, and kills millions every year in both outdoor and indoor
>pollution
There are many serious aspects of the environmental crisis. One could also add the threat to the health of the ocean, the threat to aquifers, agricultural issues, etc. It is an incredibly ignorant and conservative policy to downgrade one environmental threat by saying that there is another. All these environmental threats have to be taken care, and this requires opposing the market-based measures that are currently used, and which are paving the way to total environmental diasaster.
That said, it's astonishing to see such a casual attitude to carbon emissions when global warming is already a fact, when it is already having climactic repercussions, is already acidifying the ocean, is already threatening to drown several particularly vulnerable countries, and so forth.
> while we waste time worrying about making slight cuts to CO2 output -
Last year, 2010, there was a record increase in carbon emissions, not a slight cut.
That said, a serious environmental policy would not piddle around with simply slight cuts. It would call for serious environmental planning and regulation, rather than the market-based measures such as cap and trade or the carbon tax. It would mandate and supervise major changes in industry and agriculture. And it would to the be linked to the protection of mass livelihood: this is not just a matter of preference, but essential for the policy to succeed, because only the working masses can provide a suitable support for the needed changes. All this would require a certain measure of overall economic planning as well as environmental planning. And it would all turn out to be a fraud without mass working class pressure and participation, or else the bourgeoisie would not only evade the regulations but use them as a tool to squeeze the masses.
This goes against the logic of capitalism so, like most other major reforms, can only be achieved partially under capitalism, and only by mass struggle, and will always be under threat of being taken back. But this is what is necessary to deal with the environmental crisis.
> biodiversity is important only in the sense that preserving historical
> monuments is, as a matter of taste and preference.
Only in the sense that preserving an earth that is hospitable to human life is a mere "matter of taste and preference". After all, the planet itself doesen't care whether humans thrive or go extinct....
> Our lives will be poorer for the absence of rainforest creatures mostly to
> the extent we choose to care about them, which is fine but worthy of
>charity not political agitation.
Try at you may, you won't stop political agitation on the environmental crisis.
>
> The problem with an putative working class environmentalist movement is
> obvious - the working class does not want to rise up on behalf of the
> proposition that it must consume less.
That's the neo-liberal version of environmentalism. In contrast, serious measures to deal with global warming and the other environmental problems, measures of the type I have outlined above, would provide a better and more secure life for the majority of the population. The advent of overall environmental and economic planning, integrated with planning for mass livelihood, could provide a better and more secure life for the majority of the population: better schools, workplaces, recreation, health care, natural areas, security of existence, and so forth.
There may in fact be real scarcity when major catastrophes strike. If global warming proceeds unchecked, if biodiversity is destroyed, and so forth, there will be major suffering. In that case, serious environmental steps of the sort mentioned above will be the only way to minimize death and suffering. These measures will not be aimed at cutting mass sustenance further, but at preserving whatever mass sustenance is possible.