Fight or Flee?

Why do i sense a "fight or flee" situation right now?  It's a nagging feeling I've had for months.  I know that there is this some one thing out there (aside from the fact that there are many things going on in the world but somehow, this some one thing is going to be different).  Picture this some one thing as a giant snowball that is perched on top of a hill and is inching its way forward.  It's almost to the point where the slightest breeze or vibration will push it over the top.  It's almost there and when it does start to roll downhill, it will only pick up more and more speed, gaining all the momentum it needs to hurtle down the slippery slope and smash itself into a million pieces when it hits bottom.  Then what?  All I can say, is "oh boy."    
Why do i feel that somehow, we're being "set up" (maybe a better description would be "we've already been set up" for some kind of a huge, huge fall?  Something that is almost unfathomable.  Something that is going to be very, very hard for us to wrap our brains around.)  It's like watching dominoes that are neatly stacked together and all it takes to get them moving is a sleight of hand.  The eye is mesmerized as it watches this once neatly stacked array completely unravel in a few seconds.  Is this a future out of this world event I am feeling?  Or is it a government thing?  I believe the two will be intertwined.