who do I know to vote for at all levels of government if I don't follow US politics? How do I know what to do with my money if I don't follow world finance? How do I know where to vacation and where not to vacation if I don't follow world news? Those are fundamental questions (and yes, you might respond that I could just "ask an expert" -- but come on).

A more fundamental question is what really constitutes knowledge. Haven't you ever found yourself talking to someone and quoting a news article only to find that they've got personal experience that invalidates it? Following US politics doesn't tell you much about which campaign promises will turn out to be lies, world news won't tell you how not to get mugged in your own town, and hell, the best financial forecasting in the world is still pretty close to 50/50. I believe this to be the fundamental reason why reading the news is sometimes bad for you: it can lead to a false sense of certainty about the world and then distress when that illusion is shattered.

Even an understanding of the world that comes from direct experience is sort of a statistical inference that assumes that past behavior accurately represents what will happen in the future. Trusting other peoples' interpretations of interpretations of dispatches of firsthand accounts from across the world is just an aggregation and layering of somebody else's inferences. And on that topic:

Essentially, all models are wrong, but some are useful - George E. P. Box

Life is easier with fewer expectations that you know exactly how things are going to play out.