I don't know what movie you're talking about, but there was a twilight zone episode similar to that.
"The Monsters Are Due On Maple Street"
Maple Street, U.S.A. Late summer. A tree-lined little road of front porch gliders, barbecues, the laughter of children, and the bell of an ice-cream vendor. At the sound of the roar and the flash of light, it will be precisely 6:43 P.M. on Maple Street... This is Maple Street on a late Saturday afternoon, in the last calm and reflective moment - before the monsters came."
After what is believed to be a meteor flies overhead, Maple Street experiences a total power failure. Pete Van Horn leaves to find what is going on. Tommy, a reader of sci-fi, says human- looking aliens have infiltrated Maple Street. No one takes this seriously until Mr. Goodman's car cranks for a few seconds. Suspicion falls on him, made stronger by a neighbor's memory of seeing him looking up at the stars at night. Everyone begins to panic as the evening approaches. When a mysterious figure walks towards them in the dark, Charlie Farnsworth takes a neighbor's rifle and fires. The mysterious figure turns out to be the returning Pete Van Horn. Charlie is then accused of being the alien, then Tommy, then total madness breaks out. As various house lights flash on and off, rioting breaks out. Two nearby aliens watch these events. One tells the other that by manipulating electricity, it is easy to turn neighbor against neighbor. Maple Street is only the beginning.
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The tools of conquest do not necessarily come with bombs and explosions and fallout. There are weapons that are simply thoughts, attitudes, prejudices - to be found only in the minds of men. For the record, prejudices can kill and suspicion can destroy, and a thoughtless, frightened search for a scapegoat has a fallout all its own - for the children, and the children yet unborn. And the pity of it is that these things cannot be confined to the Twilight Zone."
Even more true now in this era of mass media and sheeples blind obiedience to the media whore. IF (Dan Rather/Peter Jennins/ other talking head) say you're a (Sexual Predator/Drug Lord/Militia Nut/Terrorist/Whatever) then you're F****d. No matter how much you protest your innocence, the sheeple will never hear of it because it's not going to be on the talk shows or the 10 o'clock disinform...I mean news.....program.
I don't think the US is going to go to hell overnight, it'll be a very gradual slide from first world democracy to third world police state over the course of a lifetime, one freedom and right at a time being exchanged for "safety" :barf: from the threat de jour(Sexual Predator/Drug Lord/Militia Nut/Terrorist/Whatever).
This in turn will either trigger another civil war/revolution, or it'll collapse into somalia, writ large.
Not that I'd rule out mutant zombies or resurrected dinosaurs rampaging.
I just prepare for the daily assualt on good manners by punks, theives, and criminals. Anything larger is out of my concern.