You do realize that tens of thousands of years is still a long time right? 10,000 is only how long civilization (as we know it) has existed. Prior to that we were Pre-Historic living in caves and like nomads.
But if you look at an average rate, 100m in 10,000 years is 1cm per year. Compared to the last century or so:
Which says 2mm/year on average. We are freaking out about sea levels rising at 20% the rate they have in geologically recent times. (and with zero pollution to boot)
What I'm saying is that the modern warming, whatever the cause, is insignificant considering the changes humans have survived and thrived under. So again, why is this bad?
And I still would like to know why we define an artificial ideal at X temperature and Y sea level, when climate and sea levels change all the time, and drastically at that. Who are we to say what it should be, aside from the normal human dislike of change?
So are you saying mankind has jack to do with the rising temperatures? Explain the ozone hole to me (which is now patching up thankfully)...
I would say, as Peter accurately surmised, that it makes no difference. People need to acknowledge there are larger forces at work (such as the sun, whose output is not constant either, and probably many things we do not understand). Any impact we may have is insignificant among all these other systems.
As GiC said earlier, would enacting all these countermeasures do more harm than good? Probably, because we do not know if it will do any good. If the sun is going through a hot phase, or of sea floor building is raising ocean levels, we could go back to the caveman days and the earth would still be changing.
I don't know enough about the ozone layer to comment.