Ice Age

When I heard Al Gore talking about the global warming a good while ago (therefore I can't find the link again of that particular talk), something that kept being on my mind since then is:

While he was explaining world history, melting of ice and the increase of temperature he also mentioned that a next step (talking in millions of years) after a global warming is an ice age.

So, if we do now have have to expect a global warming of a size and speed that never has happened before in world history - couldn't it be possible that the next step is following as fast?

If I think of control engineering and if I would be able to control the world, what would I do NOW? - Knowing that people created massive reasons for global warming, I would do everything to cool down the world. - Al Gore mentioned that after global warming the typical way weather happens then change and all the ice is rebuilt (not only on the poles). So if I would be mother nature I would already in advance do some change to advance too much of global warming.

When people talk about global warming I often get the impression that people believe that world reacts very slowly to all changes and is always behind. I don't think that changes in the world are always just lacking behind.

What, if the triggers for the next ice age already have been initiated? What if our massive contribution to causes of global warming are already also triggering the next ice age in the same speed?