Trivia: According to the Director's commentary, Twentieth Century Fox Film Corporation did not want the film to be released under the title "Independence Day" to avoid legal complications (specifics weren't disclosed as to what the problems might be, but it's also why the abbreviation "ID4" was used). Roland Emmerich (director/writer) and Dean Devlin (writer) needed to justify the title, so they added the rousing bit right at the end of President Whitmore's speech at the hangar when he ends with, "The 4th of July will no longer be known as an American holiday...today we celebrate our Independence Day!"
Trivia: When Steven and David are being chased out of the alien mothership, David says "Must go faster, must go faster." This is a line Jeff Goldblum said in the film Jurassic Park (1993), when he was riding in the back of a jeep, getting chased by the T-Rex. That line from Jurassic Park was loved so much by ID4 filmmakers, they looped it into the dialogue. Jeff never actually spoke that line when ID4 was being filmed.
Trivia: In Area 51 there is a large screen displaying the results of the nuclear strikes against the alien ships. Look under the screen and there is some text in green. Pause it to read the following: "The purpose of these green lines is to lead you to believe that these words mean something", and "And can I see with eye serene the very pulse of the machine Wordsworth".
Trivia: A promotional piece that aired in Spain for this film set off a "War of the Worlds" type of wide spread panic. The promo featured a popular Spanish news anchor and the piece ran as if there really WAS an alien attack to occur on July 4. People believed the broadcast and panicked until officials spread the word that this was only a promo for a US movie. Confirmed on DVD commentary.
Trivia: When the First Lady is hopping in the helicopter to fly out of L.A., another helicopter is nearby. It flies past a building that has a large IBM logo on it. People are standing on the top of the building, giving the impression that it is one of the first buildings to blow up. Remember that the movie was sponsored by Apple.
Trivia: The bomber that drops the bomb on the alien ship in ID4 is the direct descendant of the one that does the same thing in The War of the Worlds (1953). The earlier craft is the B-49 "Flying Wing," developed for WWII but never produced; it served as the inspiration for the B-2 "Spirit," both designed by Northrop. It was said that Jack Nothrop, the company founder, had eventually left the company bitterly with his dream design shelved. More than twenty-five years later he receives a surprise call from the new company heads for a special presentation. They give him a scale model of their newest and most advanced aircraft - the B-2. With tears in his eyes, he declares, "Now I know why God has kept me alive all these years." Months later Jack Northrop passes away.
Trivia: The reason for the introduction of the 'biomechanical exosuits' was that actually two alien designs were presented to Emmerich, but since he liked both, the more monstrous design was used for the suits.
Trivia: In the scene at the start (look carefully) just before Steven Hiller notices the alien ship, all of his neighbours are packing up and leaving. There is a mailman delivering the mail to one of the neighbours. Always delivering, come rain, shine, or aliens....
Trivia: The director asked for input and advice in dealing with some of the subject matter of the film, primarily concerning the use of Jets. However, the United States Air Force refused to cooperate with any aspect of the filming of Independence Day due to the fact that a greater portion of the film revolved around Area 51, a highly classified subject.
Trivia: ID4 follows the same pattern as War of the Worlds. First when they come to Earth we don't know what they are until they attack. Second there is a battle between an army force and one ship, and the ship wins. Next a bomb is dropped on one and in both movies they survive. And the aliens are killed by a virus in both (albeit of different types).
Trivia: The role of Captain Jimmy Wilder was played by Harry Connick, Jr. But it was Matthew Perry who was originally cast in that role. He couldn't work around his shooting schedule with Friends. But he didn't back out before he could add his own touch to the movie. He added the "Hold me" line and the head on Will Smith's shoulder to the script during the briefing scene.
Trivia: At the moment Julius gives David the idea for the virus, David stands there, grabs his head and then turns his hand in a peculiar way. According to the commentary, "For those who can't quite figure out that weird thing he did, he just turned his thinking cap around. Goldblum comes up with the greatest, coolest, weirdest stuff. He's an absolute joy to work with." (01:44:10)
Trivia: Other science fiction movies are referenced in this movie, and some scenes pay tribute, in the scene after the nuclear blast, there is a shot where military personal are looking at the results using a night vision camera. If you look, you will notice the remains of the streetlights are bent and resemble the (laser shooting telescopic) eye of the alien ships in the original War of the Worlds (1953).
Trivia: When Steve is dragging the unconscious alien through the Bonneville Salt Flats, at one point he shouts out "What the hell is that smell!?" This was not in the script, but rather Will Smith ad-libbing in response to the strong sulfur-like smell emanating from treated wastewater near the Great Salt Lake. (01:07:40)
Trivia: Despite looking massive and complex, the "wall of fire" traveling down the streets during the initial attack was actually an incredibly simple effect to accomplish. The crew would build models of the streets, mount cameras to them, then simply turn the model 90° so they'd be vertical. They would then set off pyrotechnic charges at the base of the vertical model, and the fire would naturally flow upwards through the model buildings. But from the perspective of the mounted cameras, this created the illusion of the fire moving horizontally.