An interesting idea from the authors of the above article. Aliens wind up extinct pretty quickly.
It’s also possible they’d wipe themselves out, which is a potential danger to us too.
As I’ve mentioned in a discussion I’ve been having (one which has touched upon the importance of and uniqueness of life), regardless of whether you feel humanity is a divine creation, or whether we are a one in a million shot, we are special. There is only one planet with humans on it, and we need to look after this rock – and ourselves.