There have been all these articles recently, in the wake of Stephen Hawking's new show, Into The Universe with Stephen Hawking, about how Hawking says that the existence of aliens is essentially a mathematical inevitability, and we shouldn't necessarily be broadcasting our presence into the far reaches of space because it's foolish to assume that these extraterrestrials are benevolent beings.
I've been saying this for years! They can't all be as nice and hilarious as Gordon Shumway! Shut up, NASA (or whoever sends radio waves into space announcing where to find us)! We don't want aliens to know we're here! If they're anything like us, and they already have the supremely advanced technology it takes to reach Earth, then we're totally F'd in the A!
Hawking said, "If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn’t turn out very well for the Native Americans." Here's a link to one of the articles: