Any civilisation which is capable of traversing such distances is far in advance of our own. They could likely make the choice between annihilating us or parenting us.
Or stayin' the hell away from us. If I was some alien dude and discovered that an alien life form's (inhabiting that little blue marble third from the little sun) greatest achievement was the capability of completely destroying themselves, I reckon I'd just leave well enough alone.
Well, at least we can all lift a glass of Pan Galactic Gargleblaster in celebration of Towel Day tomorrow.
Lol! What?
http://towelday.org/