I figured that an alien invasion is very unlikely. Because I looked at the reasons why another country invades another country here on earth. Like for Political, strategic, and religious reasons, to gain natural resources (*cough* Iraq *cough), or if one nation believes that an other nation is to be a real threat.
All but one doesn't apply to us. For example we haven't interacted enough for politics to be a cause.
I highly doubt that they would invade for resources. These beings have technology to speed across the galaxy for billions of light years to get to earth. Also they can mess with gravity and other quantum forces, and they probably could literally turn water into whine with their super advanced tech. Besides even if they couldn't there are plenty of dead lifeless planets they can mine from so they don't need to pick on poor little earth.
For strategic reasons is just as doubtful. The galaxy is so big that the location of one planet is not going to matter, and they have nine to pick from and not to mention countless moons revolving around them. So if they need to use our solar system picking mars is just as good. So even then earth isn't a problem.
And us being a threat is laughable. They are so advanced in comparison, they can travel light years in an instant, but the farthest we have ever gotten is our own moon. We are hardly a threat, if they wanted us gone all they had to do is drop an asteroid on us and good-bye humanity.
Only reason i could think of is extraterrestrial zealots of an alien religion Like halo's Covenant or Stargate's Ori. That sweep the galaxy forcing other races to convert, and/or commit an galactic genocide for their god(s). Zealots are unpredictable, never make sense, and cannot be reasoned with. This ET is our only real threat. Yet the chances of that are astronomical.
And for other reasons why ETs invade for that us suggested in sci-fi movies. Like making a new home for them, conquering, and getting human slaves is just as unlikely if not more. They probably can easily terraform a dead planet than invading ours.
to conquer... well let face it this planet isn't that extraordinary. Except that this planet in only one we know of that has life. This planet doesn't have any real value. The inhabitant's technologically is primitive in comparison, and resources we have here can find be fond on any other rock, and as for riches. What we might find valuable here may not be the case with them, and picking on defenseless planet isn't worth bragging about. People who conquer do it to gain something, like materialistic wealth and honor.
And as for human slaves, they can build robots to do their work for them Robots are better slaves than humanity is because they never get tired, and will never need to eat, drink, or sleep. Only thing that is required to keep them working is rutine maintenance.
So if we are not something for them to kick around, then what are we to them?
To them we are like what wild animals or the primitive tribes in South America are to us. We are some thing to study, to observe. They are watching us, because they feel that we are worth learning from. This is probably why they never actually interacted with us, because us learning of their existence will ruin their study of us. The same reason why ETs have been abducting people and experiment on them to learn about our physiology.
They probably ease drop on the countless radio signals we put out every day. They watch us form their ships, and wondering the meaning behind our many behaviors.
Okay now I'm done, that has to be my longest post yet.
