The sunrise cometh?
Every once in a while, I can't help wondering what is the point of stating the obvious.
If something has been happening cyclically for hundreds of millions of years, why does a repeat warrant any kind of a discussion?
Ordinary people can experience the periodic nature of the sunrise (although that too is not as simple as it might at first blush seem, the time varies on an (almost) yearly basis for example, and the point on the horizon where it occurs also varies on a yearly basis). They cannot experience the periodicity of the ice ages. Therefore they need to be convinced of their existance, which is one point of having a discussion. The other point is understanding causation, which in turn can improve prediction of the next event. If you knew it was going to happen in the next few years, you might invest in land in Arizona, Mexico, or even central or northern South America. Or at least make sure you have a parka, snow shoes and lots of insulation.