CNN.com: 'Battlestar Galactica' at the UN

Fantasy and reality will collide Tuesday night at the United Nations, as writers and actors from the Sci Fi Channel's hit "Battlestar Galactica" meet UN representatives to discuss issues such as human rights, children and armed conflict, and terrorism. Also on the agenda: dialogue among different civilizations and faiths. The meeting happens just days before the two-hour final episode of the show airs Friday.
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"Traditionally, sci-fi has always been an opportunity to look at the human condition, and then extrapolate out. Science fiction has always held up a mirror to society and to humanity, and has asked tough questions about where are we going, and whether we're going in the right direction, and that's the nature of Battlestar Galactica," Howe said.

I think the last paragraph is what makes science fiction shows great.  It's not the space ships or battles, but a different way to look at human drama.  To explore conflicts in a way that's not possible when using contemporary characters.