These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Mars Attacks!
Adaptation Displacement: The trading card series from the 60's and the comic series from the 90's are known well among pop-culture geekdom but most people recognize these aliens from this movie.
Acceptable Targets: Congress. In-Universe, at least one human finds their slaughter at the hands of the Martians hilarious, as did many of the audience members.
Alternate Character Interpretation: Was the translation machine built by the Martians actually effective at translating their messages, making them lying liars, or was it just consistently mistranslating their warnings of impending doominess as messages of peace?
Or maybe, unable to ever get the machine's bugs sorted out, the human scientists just played a recording at the landing ceremony to cover their own asses.
Also the Martian Leader's reaction to the President's big speech. Was he just fucking with him For the Evulz, or did he genuinely gain a bit of respect for the president in that scene. Notice how the Martians aren't overtly sadistic or mean after the speech. Maybe they gave him the closest thing to a noble death they could comprehend.
The novelization gives an answer to the above questions: the Martians are lying through their teeth any time they say they come in peace. Destroying planets is the entire basis of their civilization - it's their reason for living.
The Martian who killed Danny DeVito's character, he seems to be contemplating his proposal before he decided "ah screw it, I wanna zap him".
The Martians may be redneck trailer trash like Ritchie's parents, and a Flying Saucer is just like a pick-up truck to them.
Grandma might not be such a space case - she might just have a uniquely mordant sense of humour.
Darkness-Induced Audience Apathy: Variation: The cast is loaded with self-sufficient, bombastic Jerkasses. This is so we don't feel sorry when the Martians kill all of them and feel good about the ones which are genuinely good mostly surviving.
Fridge Brilliance: When nuclear weapons are used against the the Martians they capture the explosive force of the nuke, and smoke it! They actually get high on radioactive explosives. Fridge Brilliance kicks in when you realize that a hydrogen bomb really does produce helium as a by-product of nuclear fusion.
Fridge Logic: How come Donald Kessler and Nathalie Lake's heads can breathe if it's been established the Martians breathe nitrogen? Why are they alive at all?
Conversely, why CAN'T the Martians breathe on Earth considering Earth's atmosphere is in fact 78% nitrogen?
Allergies to the remaining 22% of stuff? Could be some thing as simple as an oxygen allergy?
Harsher in Hindsight: There's a shot of the World Trade Center 15 minutes into the movie. In a blink-and-you-miss-it shot later on, we see the Twin Towers tumbling over like giant dominoes.
Hilarious in Hindsight: In the ending we get Natalie Portman giving the movie's true hero a medal and kissing him this was before Phantom Menace but seems like an accidental reference to it.
If you've played Team Fortress 2, Tom Jones' cameo will probably result in a giggle, as mentioning him is somewhat of a Running Gag in the supplemental comics and videos. Though where Tom Jones shows up to be a badass in this film, in the comic Unhappy Returns he instead spends one panel alive before being abruptly killed off.
Inkstain Adaptation: There are fans of the original Mars Attacks cards who don't care at all for the film's comedic tone.
Moral Event Horizon: The Martian ambassador was brought into the White House claiming to apologize for his people's misdeeds. What does he do? Reduce everyone to skeletons.
The Martian Emperor when he turns down his chance for redemption and impales the President in the chest with a flag.
Nightmare Fuel: Any online discussion of this movie will inevitably devolve into a rundown of just how many kids had nightmares of the Martians hiding in their closets or outside their windows. Their Uncanny Valley appearance of a skeleton, their violent ACK ACK language, and the sheer glee with which they mutilate/disintegrate humans have haunted the dreams of children throughout The Nineties.