So here is my problem with little green men, not the fictional ones, the real ones:

1. Regardless of your perceptions of probability, there is no evidence of life elsewhere in the universe.  That bothers many people.  They WANT there to be life elsewhere.  Recordings of data have a way of being distorted to meet the WANTS of the data takers and interpreters.  Wait for the truth.  Don’t devalue it with WANTS.
2. War is almost a law of Nature in itself.  I do hate to say it, but the will to survive leads to competition to survive, which leads to wars.  If there indeed is life elsewhere, it will be as warlike as we are on this planet.  There is no reason or evidence to support any other theory.  We are the only DATA, and we are pretty convincing.  It may not be what we WANT, but DATA is FACT.  Oh, did I mention that war is expensive?
3. Space travel is expensive.  For that FACT, we have overwhelming DATA.  To think that it is different on some other planet falls into the WANT category.  Our DATA predicts that their economics are similar to ours.  We have no other DATA.  One should expect that they have debt crises, just like ours.  They have other priorities, just like we do.  Even if the technical challenges were easy, they can’t afford to get here anymore than we can afford to get there.  Show me a real wormhole that can bypass the economic reality we live in, and I will reconsider the issue.  Just keep in mind that its life cycle costs have to be low, very low.  It must cost only a very small percentage of the GNP, not the whole thing.  I will not vote for anything that bankrupts planet Earth just so two guys and a woman can travel beyond the speed of light, only to be eaten by the little green men when they get there!

So, keep on with the fictional little green men.  They’re the only ones who don’t require reality.  Nature and your wallet do!