"It seems to me that when it comes to doing something which we know will mean thousands of people being killed, a higher degree of evidence is needed than when it comes to stopping doing things which we have reason to believe may be killing thousands of people. "

So. potential deaths in slowing global warming would be ignored, as would potential lives lost in NOT doing anything to make Saddam comply with the UN resolutions?

The DANGER of Saddam with WMD was far greater than the DANGER of global warming- potentially millions of lives, certainly ( already ) hundreds of thousands. The "evidence" that global warming has a significant impact on hurricane strength is considered phony by those who should know- see my quotes on the topic in various threads. You are argueing that we should take action on evidence that the best authorities agree is not definitive- YET deny that the US should take action as per UN resolution where the evidence was a lot less clearly fals?