You may think the world is more dangerous than it is, as you've been consistently exposed to news about crime, violence and terror.
One may rationally know that the news is mostly about the extraordinary (the ordinary is rarely newsworthy), yet still unconsciously have a biased view of the world as a dangerous place.
Remember that for every instance of danger, another of kindness exists - though it's probably not televised. I believe whether you are pessimistic or optimistic is mostly a question of how well you understand this idea of unlimited evidence and limited portrayal.
There are many more concepts in my "Mind Expander" tool (it's free)