Why is there a danger that a large asteroid might strike the earthat some time in the future?
All of the evidence seems to indicate that’s -exactly- what whacked the dinosaurs (and about 70% of all of the rest of the life on Earth) about 65 million years ago. The danger is that they really exist and they really are out there. And we’ve had a few pass fairly close (within a million miles) in the last few years. The bigger danger (to the majority of the half-witted fµckmonkeys on this planet) is that someone will start predicting that it will happen in 2012 and everyone will shell out lots of money to buy their book(s) and videos about how to survive.
