Brothers Judd has a post on the waning of the Kyoto Protocol. As always, two thoughts occur to me.
The first is that this is another example of how the citizenry of a liberal democracy get things right. In the short term, of course they are subject to random swings of opinion and fads, but in the long run the truth will tell. It’s much like the stock market, whose accuracy in valuing companies increases in direct proportion to the timescale on which you take measurements.
The other is from one commentor’s note that the next big environmental “crisis” will probably be self-replicating nanobots. The concerns about this are another reflection of much of the magical thinking that goes on with respect to nanotechnology (here for instance). Nanotech will be amazingly powerful and in many ways magical to us, but it’s still has to work within the confines of physical reality. The “grey goo” problem exists only if one doesn’t think about the energy problem with nanotech, which is where are all those self replicators going to get the energy to support unlimited copying? If grey goo were a real problem, we would be living in a sea of bacteria, which are very good at sef replication.
Of course, there will be nanotech based environmental disasters, just like the oil economy has oil spills, or (to use my just previous analogy) we have bacteriological crisises (red tides, plagues, etc.). These will be serious and we should certainly think carefully about nanotech and try to prevent such disasters. But an existential threat? No.