I'll go ahead and specify that this is more a parody of the the DLC game for Battle: Los Angeles than the movie itself. I'm hesitant to make fun of stuff I haven't actually seen, but thanks to YouTube and some playthroughs...god, my eyes!
Just For Fun
Throughout this entire invasion, no-one's asked why the aliens have invaded Earth.
Some people had said it's because of our water, that they want to use it as a fuel source. To those people, I call them idiots. If aliens want water, why not land on Europa or Mars and extract it without fear of indigenous reprisal. And of course that's assuming that there's nowhere else between this world and Planet X where water can be found in some form or another. And that's assuming that the energy spent getting here in such numbers will make such an operation viable. And that's assuming...well, you get the idea.
And if the aliens really are here because of water...well, I have to ask as to how they came to be so technologically advanced if they're willing to invade a planet because of water.
But I digress. It doesn't matter why the aliens have come here. This is the real world, where plot devices don't have to be provided for us like an interested audience. No...our job is to go through Los Angeles (which always seems to go to hell in films...Terminator, Blade Runner...) doing...well, I'm not sure. You see, when you're being briefed via comic-style animation, you tend to drift off. Yes, I'm serious-comics. Man, at this point in time, I don't know which species is more idiotic. But anyway, we're trudging through, just our squad, fighting...walking phlegm? Wait a minute...we're under attack by phlegm? Was Spock right all along, that's its life, but not as we know it? Except...we do know it? Heck, I don't know. All I know is that for some reason, we have only four types of weapon to deal with the walking phlegm that looks even less detailed than the more heavily armoured aliens visions have seen. You know, the ones with weapons grafted onto them. Man, imagine what the kids must look like...
So on it goes. Trudging, firefight, cutscene, then back to trudging. And more trudging. Then a firefight, and...well, you get the idea. So maybe in my court martial you'll understand why I started shooting the scenery for kicks, to watch pretty explosions. Waste of ammo, destruction of property, negligence, etc. But the entire routine was just so boring. Heck, after fighting walking phlegm for hours on end, shooting at anything apart from aliens became more entertaining.
But maybe there lies the key. Maybe I've sussed out why the aliens are invading. Maybe it's because they're just like us...
...because maybe, they like blowing things up for the sake of it.