Quite true. Of course, there's no reason to assume you will not be physically harmed either.
I believe there is a good reason to assume I wont be harmed, as I mentioned when talking about the peaceful enlightment.
It's actually pretty likely that more species that have the tech for interstellar travel would be a war-like species, as (at least on Earth) war and strife tends to advance technology faster.
It's true that war advances technology, but a species can't learn if it doesn't make mistakes. That's the upside of hisotrical atrocities in my opinion. More and more people learn from them every time they happen.
And even though war advances technology very fast, who's to say a peaceful society didn't simply survive "long" enough, as in hundreds or thousands of years finally getting that technology. Not to mention curiousity, over population could potentially drive that technology just as fast as war does. And think of the combined resouces of a one world government, that no longer has to divert resources to war, when compared to a world like ours currently is. 300 million Americans spend fifty cents a year on NASA. Imagine if 7 billion earthlings spent 50 cents a year on NASA, in a world without poverty. That would bring interstellar travel a
lot faster than if we simply go to war all the time.
So in theory world peace should bring interstellar travel faster, than world war.
But assuming that they'd have 'scaly or leathery green skin, and huge black eyes, long skinny bodies and freaky appearance' or that they looked 'gross' isn't predjudiced and stupid?
Some people think pizza taste good, and some think it tastes gross. It's a matter of your taste buds. Just like some people are sexually attracted to their own gender, and others, their opposite gender. It's a matter of sexual instinct.
Standards of attractivness are nothing more than programmed instinctual feelings. A dog is attractive to a dog, and a human is attractive to a human.
Imagine if the alien looked all slimy? Or if it looked like the aliens in the movie Aliens. Even if it's peaceful my instincts will say to me "unattractive" and chances are their instincts will say the same thing about me.
I'm not saying their factually gross in the universal sense. I'm saying that they wont have "human" beauty, and I wont possess their natural definition of beauty either. It doesn't mean we can't coexist peacefully, and it wouldn't make us prejudice either. Some people are more physically attracted to hispanics than other races, for example. That doesn't make them racist. Just like being straight or gay, doesn't make a person prejudice against a gender. I think penises are gross. That doesn't mean I'm prejudice against men.
If you mean that I'm assuming all alien races look the same, the no I'm not. They each probably look different. I merely meant that they will look so different we will probably find them creepy, untill we get used to them.
edit.. despite the fact that war drives technology and even space technology, it would never prmote intersellar travel. Think about it. Your either peaceful before you go interstellar or your not. If your trying to kill people in Africa or the middle east, or China, then why would you go to Alpha Centurai? All of our military space efforts are aimed at spying on earth, delievering destruction on earth, and probably soon, gettin from one location to another on earth. But war would not provide any motivation for going interstellar.
global warming, impending asteroid doom, over population, the sun going nova, would all promote interstellar travel. And if a society doesn't find world peace, none of those reasons would ever matter, because they would blow themselves up long before those situations pose a threat.
read what I wrote, then read your response..... WOW..... 
I'll check eBay to see if they have a Sense of Humor you can bid on.
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