Yeah when we discuss global warming I think it is a great idea to ignore the fact that the Earth was much warmer before the Ice Ages. Yeah we can all agree there was some event that helped put the earth into an Ice Age but why hasn't anyone ever asked if It was warmer here before the Ice Age wouldn't it be almost natural to expect the Earth to gradually return to what it was before the event before man was here to supposedly create a problem we refer to as "global warming". Almost like a spinning top a slight jolt can cause its motion to be erratic but it eventually rights itself?
So again the model is Really Warm (dino era) >>>>Big Event makes it cold>>>> gradually the earth is returning to what it once was.
IMO it would probably do this with or without us. We just want to pretend that since it is better for us the way it is now that this just has to be how it is supposed to remain forever