Have you ever heard of Filter Theory?
It's a sidenote to the Fermi Paradox that attempts to ask the question "where are all the aliens?"
Filter theory says that as the basic ingredients for life are the same everywhere, and the Universe is billions of years old, there must be a particular barrier that it's extremely difficult for life to hurdle over on its way to becoming what humans are now. Otherwise we'd see aliens everywhere.
Some people believe that that barrier is way behind humanity and in the very early stages - the merging of mitochondria and single celled organisms into a symbiotic cell that allowed for complex multicelluar life to emerge is a possible contender for where the filter is. However, there are some who believe that the filter is actually in front of humanity. That civilizations rise up all the time, all over the Universe, but then hit a certain point whereby the same evolutionary desires of competition and exploration that allowed them to colonise their entire planet will lead them to ultimately develop weapons that can destroy it.
It's an interesting idea. There's a filter SOMEWHERE along the timeline of humanity. It's just a debate about exactly where it lies.