Note the massive, schizophrenic disconnect pointed out by Robert Felix in his analysis of the article. The author thinks that "disruption of agriculture as a result of having no sun could be, like, serious." Yes, you could say that, if you consider billions dying from starvation and half the planet turning to cannibalism, yes, it could be serious n'stuff.
The Sun provides the energy for the entire merry-go-round that has led to population growth to six billion people. If it declines in output and stays there the way it does outside all interglacials, this party is going to stop really abruptly.
As Felix pointed out, we'll be fighting in the streets over food (and oil and water) before the next Ice Age formally begins. Nuclear war is a given, it will absolutely take place in the massive struggles between nations to control what little remaining fuel and food there is to go around.