I don't think we all doomed and it is possible that the human race may have a great future. This was forecast in Olaf Stapledon's book First and Last Men a book that greatly influenced Arthur C Clarke. Just as other species we share our world with have periodic collapses so eventually will the human race,but each time it will be that little bit wiser. In the book we experience 18 over the course of several million years until the Sun goes nova and a final extinction occurs.