And the direct source of the movie...

Rating: 10/10 (8 October 2007)

The actual direct source of the movie is Gordie Dickson's Hour of the Horde (c) 1970, although there's a good bit taken from the War of the Worlds, circa early sixties.
From the back cover: "annihilating everything before it, a horde of monstrous space travelers were advancing through the stars. And Earth lay in their route...." Lots off nukes and computer strategy, but it's people getting beyond what held them back to become more that defeats the horde.
Go read.
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