Say you were in a 5 man recon element who spent the night watching 100+ dismounts with armor and assorted technicals rape and kill everyone in a small town across an imaginary line. Skip ahead to the silent morning, nobody screams when they're dead. Post sunup half that motley group decides to go cross country across said imaginary line towards you instead of back the road they came. You can't break cover and your air assets are 27 minutes out with about 2 clicks till they're on you. You can smell them. They are coming. That my friend is shtf.