The little verifiable evidence I've seen presented for alien contact tends to be summable as "I don't know how people managed this, aliens must've helped."
I find it rather unconvincing.
This is a fascinating and scary way to look at things. I do believe we have the capacity to engineer our own demise as a species. It may be nuclear Armageddon. It may be biological bloody death. It my be by tinkering with our or other DNA and unleashing something unforeseen. It might be while trying to create black matter. Or it may be when we unleash AI on ourselves and Skynet becomes self aware. Whatever it is there are many options and that is scary.
That was an interesting take on why we can't make contact - everyone killed themselves but since our universe is so big its still probable that a lot of life don't know how to kill themselves, they're still in a dinosaur age.
Where life out there is in a very basic life, modern or advanced life cycle the fact that there could be and probably is life out there is something to celebrate. Now we need to figure out how we can meet more of these life forms and learn how to coexist because for some reason we seem not able to do with ourselves.
I would think somewhere in the universe there could be other life. I just hope we find them before they find us. Its not necessarily a good thing for them to find us. They might not have our best interests in mind and will have much greater capability than our planet if they reach us. I don't think that water or viruses will help us but who knows *smile*.
We may have been visited by aliens if you look at stuff that has happened in the past. I think they are highly advanced and are watching us to see what is going on with us. Are they helping to make sure we go in the right direction before inviting us to a much better future? We will have to wait and see.
If that is the case KN I am concerned. They would see how badly we are treating this planet and might decide to step in. At the rate we are going I could see us destroying ourselves as Abnninja mentioned.