The most terrifying and overlooked issue in the U.S if not the world is the supervolcano in the western US that is bound to erupt any moment. Even if you're out the blast radius, super-tsunami, super-earthquakes and the shifting of the plates will wreck so much havoc on this planet and if that doesn't scare you? The ashfall out will cover the sun and super-cool the Earth for hundreds of years.
What would you do in this situation:
"BREAKING NEWS: YELLOWSTONE SUPER VOLCANO ERUPTS"