There will be a war...or almost a war. All troops will be ready to fight. But just before they begin a large planetary body will make its presence. It will be so obvious and scary that everyone will drop their weapons and run home to their families. It will be too late at this point. Almost everyone will perish. Just a few will make it for the next cycle. I am certain this will happen. Don't ask me how. I have known this since I was a child.