Who You Gonna Call?

I was chez Abraham last night, and watched as Kat played one of theXCom series, video games about an elite force of soldiers tasked with repelling an alien invasion of what looks to be Middle America. Just as Master Chief leads the elite alien-fighting Spartans in theHalo series, and Nathan Hale leads another elite alien-fighting outfit inResistance, and an elite force of ninjas fight aliens in Ninja Crusaders.
And I thought, why hasn’t anyone made a video game in which the aliens have to be...