First there was space—endless, limitless space, so far from everything, so brutal, so frigid, so uncaring that it numbed the mind, not so much from f… - Clifford D. Simak

He needed sun and soil and wind to remain a man.

My reluctance to use alien invasion is due to the feeling that we are not likely to be invaded and taken over. It would seem to me that by the time a race has achieved deep space capability it would have matured to a point where it would have no thought of dominating another intelligent species. Further than this, there should be no economic necessity of its doing so. By the time it was able to go into deep space, it must have arrived at an energy source which would not be based on planetary natural resources.

And it was then that he fully understood that even here, in the heartland of the nation, in the farms and little villages, in the roadside eating places there was a boiling hate. That, he told himself, was the measure of the culture that had been built upon the earth — a culture founded on a hatred and a terrible pride and a suspicion of everyone who did not talk the same language or eat the same food or dress the same as you did.