Independence Day/Fridge

Fridge Horror

 * The aliens take out NORAD. Isn't NORAD under a mountain?
 * Fridge Brilliance: The aliens have a Wave Motion Gun powerful enough to take out cities in one blast. So a mountain's not much of a problem.
 * David tells Marty to get his mother out of town. Marty tells her to go to her sister in Atlanta...which is later mentioned as one of the cities taken out in the second wave of attacks.

Fridge Brilliance

 * The Roswell crash was a ship belonging to the movie's aliens. It was held in Area 51 since the 50s. Part of the conspiracy theory mythology involving the supposed aliens and alien technology at Area 51 (and possibly mentioned in the movie, it's been a while) is that a lot of modern technology was reverse-engineered from the alien technology in the ship. Put all this together, and it no longer seems quite so unreasonable that David could hack into the alien mothership with his laptop; it was probably reverse-engineered from the alien ship in the first place.
 * Similarly this shows that they have been doing Recon on the Human Race and America in particular for some time... this is presumably why the attacked when they did. Remember the comment that 40% of American soldiers are either on shore leave for the holidays or massed in Washington for the 4th of July parade? The Aliens knew that they were both unprepared and there would be a significant portion in DC so they could take a large part of their military leadership in one fell swoop. This is also why they targeted the White House.
 * It could also serve to explain why Captain Hiller can fly the alien ship. Every sub-sequent fighter-jet which came after the ship crashed was probably based on its technology in some way, shape or form.
 * In Independence Day, why are the destroyers the size of a city when the actual weapon takes up a few blocks at most? If they made the destroyers smaller they could build more and attack more cities at once. However, having a large surface just above the city being destroyed channels the energy from the central weapon, making the weapon many times more efficient. -- Anemone
 * Also, their entire civilization is contained solely in the mothership and those destroyers. A destroyer isn't a military vehicle; it's an entire military base and the surrounding town to boot. They don't just fly the things; that's their home. It makes sense that it would be built for all the size they can afford to give it, as this is where they spend their entire lives.
 * The idea of uploading a virus to the alien mothership is the subject of much ridicule. However there's actually an explanation that makes this slightly plausible, at least in terms of movie logic. When the crashed alien ship is first shown it is stated that the wreak was the source of all the modern advances of the last 50 years. Our computer technology could potentially be compatible with that of the aliens because it's based on that of the aliens.
 * Lack of security in their computer network is also somewhat understandable -- they communicate telepathically, and are "like locusts". Very probably they have some version of a Hive Mind, which would preclude the need for that much security, as no-one would sabotage themselves. They just didn't consider that one of their victims would find a way in and use it against them.