Trope-a-Day (R): Absolute Xenophobe

Absolute Xenophobe: There are some species that might feel this way, but almost none that try to act accordingly on the interstellar scale; in general, pissing off the entire Galaxy, or even that small piece of it that constitutes the Associated Worlds, is not survival-oriented behavior (see Genocide Dilemma, when we get there).  The ones that did try it out are no more, or at least back in the Stone Age; the ones who were smart enough not to are hiding under “Keep Out!” signs on well-defended fortress worlds, quietly ignored by all.