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...we have these vastly intelligent aliens who decide to steal humans from a planet that is about 70% water, which will KILL them, aliens that can't break into a simple house or learn our languages, but can travel across the universe, cloak their ships in the sky and shoot poison gas out of their wrists...aliens that are physically weak but decide to invade us on foot, no weapons, and make as much noise as possible in this attempt to steal our bodies when they could have easily done it without anyone knowing about them...you can say he was trying to keep the aliens mysterious, but I saw it as him making the aliens utter retards in order to set up his suspense without really thinking things through...
We know nothing about the aliens, except what we see through blurry, tiny TV snippets. Nobody knows <i>why</i> the aliens are here. Maybe they're desperate and this planet is their best choice. Maybe a somebody put a virus in their fruit loops. Who knows? The point is, we don't know anything about the aliens or why they're invading earth. Anything you assume about their supposed "vast" intelligence or anything else is pure speculation.
All that's important is they're here and they want a piece of our ass. That's it. Period. End of story. No fancy explanation. No breakdown of their socio-pcycho-econo-techno-strata. This isn't E.T., Close Encounters, Aliens, Independence Day or any of a million other alien films. We <i>don't know</i> why they chose to invade Earth. And you know what? That's OK. It adds a very interesting hue to film (apparently too interesting of a hue), but it's really not central to the real story or what the film is about.</div>