I can play linky too: http://en.wikipedia.org/wiki/Near-Earth_object#Near-Earth_asteroids http://en.wikipedia.org/wiki/Near-Earth_object#Near-Earth_as... There

I can play linky too: http://en.wikipedia.org/wiki/Near-Earth_object#Near-Earth_asteroids http://en.wikipedia.org/wiki/Near-Earth_object#Near-Earth_as... There have been many more asteroids passing really close to earth in recent history than "almost nuclear wars". My point still stands -- nonzero chance is a terrible reason to do anything.