Coronal Mass Ejections are what we should all be worried about. Many of the things you're talking about are caused by the sun and various other space weather.

Civilization is wiped out in a cyclical manner every 12-10k years. There's now significant hard geological/archaeological evidence that humanity was far advanced, then wiped back to the 'stone age' 12k-ish years ago:
[link to www.youtube.com (secure)]

It's happened many more times than just 12k years ago, but that's usually a bit too much for people to comprehend. Too far out of their reality box, so let's just stick with "We're over due" for another Solar induced dark age.