Age appropriate and all that, but if you let your child watch YouTube, browse news channels or access to to TV without vigilant monitoring, then there is a large likelihood that they'll be exposed to footage. If we, as parents, don't provide a narrative for what they see, then they'll fill in the gaps of their understanding with their own imagination, what they hear from friends or with whatever slant is being projected in what they're watching.
My two oldest were already in school, so they have their own narrative of events. The youngest was too young to remember, so when he became old enough to be aware of the world beyond our own cocoon, we began telling him about the events of that day. Our kids view so much simulated violence through animated films, movies, video games, etc., that it was important for us that our kids understood that this wasn't a game-over moment but real tragedy and sorrow for families and real consequences to entire groups of people because of the agenda and actions of a few.
Kids are self-centered. That isn't bad, just that they don't have a lot of control over their own lives and, thus, filter everything in their environment by how it affects them or will affect them. We keep this is mind when we discuss world events so that while they are taught the "bigger picture", they're also allowed to process whether this will affect their own security, safety and way of life.
