So today I watched monsters vs aliens (which is absolutely brilliant and i can recommend to anyone) and it got me thinking "why is it that all aliens ever want to do is kill all the humans and/or destroy earth?" I mean really, do they have any motive? It seems that pretty much all films/books etc portray aliens in this way. Obviously there are exceptions, like Avatar and such, but the majority of films make aliens out to be evil.
So my question to you is why do you think this is, why aren't any aliens just wanting to come and chill with us for a bit, maybe have a few brews and watch the rugby or break out the N64 for a cheeky game of Goldeneye 007 or something like that?
Also on a (slightly) related matter, how do we know the aliens in Space Invaders are actually invading? Who's to say they're not just diplomats sent to befriend the human race? I bet if you don't start shooting them in that game and just stand there they eventually land on earth, come out of their ships and say "hello, we came to chill and maybe have a few brews and watch the rugby if you're k with that
" And why, if you have 4 ships, do you send them out one at a time? Would it not be much more effective if you sent them all out together? I mean, c'mon, who's in charge of this defense?! Anyway that's my Space Invaders rant over 
So my question to you is why do you think this is, why aren't any aliens just wanting to come and chill with us for a bit, maybe have a few brews and watch the rugby or break out the N64 for a cheeky game of Goldeneye 007 or something like that?
Also on a (slightly) related matter, how do we know the aliens in Space Invaders are actually invading? Who's to say they're not just diplomats sent to befriend the human race? I bet if you don't start shooting them in that game and just stand there they eventually land on earth, come out of their ships and say "hello, we came to chill and maybe have a few brews and watch the rugby if you're k with that