Trivia: The people in the boat at the begging of the film are members of Stephen King's favorite band, AC/DC, who also wrote the music for the movie.
Trivia: The Dixie Boy Truck Stop was built strictly for the movie, and was not a functional stop. However, there were so many real truckers trying to pull in, that the film crew had to put up signs directing them not to stop by. After the filming, people got together and revamped it into a working place and tourist attraction, but closed it after a few months of bad business.
Answer: It should be noted, the ending title cards seems to set it up so there are no plot holes and answers any "why" questions (which, intentional or not by King, can be debated). While the opening premise is the comet's close pass by Earth caused all machines to turn on people, at the end, the Russians blew up a UFO 2 days later, suggesting that it was the aliens controlling the machines. Bill suggests aliens are trying to wipe out humanity (although at that point he's just guessing and had no evidence of an alien or UFO present), but it can be debated the actual premise was that aliens were just testing or experimenting on people.
Bishop73