Any asshats who truly desire such an outcome should simply do us all a favor and commit suicide at the earliest possible time.
I wish they would follow their beliefs, but most insist upon taking everyone else with them. Some just figure it is a good way to gain power - i.e. just kill off all the intelligent people so the idiots are the new elite.
Now, I won't debate your hypothesis that such people are among the AGW crowd. They could well be. But, I suspect they are likely in the minority.
I doubt most of the people of Stalinist Russia, Maoist China, or Pol Pot Cambodia were insane genocidalist either. But the leaders were and they killed millions while the lemmings sat silently by and watched. So we have another sort of megalomaniac now. And as you indicate, most are just stupid people easily lead. So any idiot will do - this was just demonstrating that the idiots are not in charge of the movement.
I do agree that the idea of deliberately stagnating the global economy, whether to protect the planet (which is seriously naive and, well, insane), or to promote some screwy left wing agenda a la Atlas Shrugged, would be globally disastrous. Positive changes come about through advancement and growth, not stagnation.
When you have the new chic being that unemployment grows the economy (willingly parroted by the sycophantic press), then what else would you expect. We have one of the stupidest men as president ever, yet the idiotic sycophants think he is brilliant because he is a slick teleprompter reader. idiocracy is no longer a comedy. It is a reality.
