This can be interpreted as a form of: "The Garden of Eden - Tree of Knowledge of Good & Evil"
In addition to the answer provided by @Little Ms Whoops, I'd like to contribute some points to think about, perhaps helping you to form your own reason.
There are definitely different views on this subject. It's your freedom to decide, and the different paths are valid. These choices will mostly likely have an affect on how your child sees the world and copes with it, and possibly contributing to their life purpose. Maybe seeing the famous photograph of the girl (Phan Thi Kim Phuc) from Vietnam running nude from a napalm strike and crying contributed to people choosing a profession in some way. The fact that you are concerned about the images shows that they have the potential to be impactful. Here are some perspectives.
- The Realist Perspective: Sheltering the child is a dis-service to them.
Not preparing them for reality that humans have set, time and time again, proving to be a violent species. When conflicts are in front of the sheltered child, they don't know how to react or handle it, because it's surprising and disturbing. Being exposed to these realities gives one an advantage over naive individuals and sets them up to recognize potential danger or conflict.
- The Protective Perspective: Sheltering the child to a point is a benefit.
Letting them focus on positive aspects of humanity while they build their core understanding of how to live and learn, solving problems without the burden of worry or awareness of atrocities.
- The Neutral or Natural Perspective: Your child will be exposed to plenty of negative influences in this life, deal with them as they come and don't rush them.
Let the child be a child for innocence's sake for as long as you can. They will be exposed to everything in the time that is fitting their existence and upbringing. ie, If you are born in a war-region, it makes sense to worry about it, but if you are born into peace, enjoy it.
- The Spiritual Perspective: You create the reality in which you live by what you choose to think about and give attention and energy.
If you want a life of peace you can have it simply by not engaging in conflict. Examining negative aspects of humanity brings them into focus, and one can find whatever it is they are seeking if they so choose. Energy follows thought.
Some things to consider: in no particular order
If your child is going to be exposed to anything undesirable, do you want to be the one exposing them to it?
Are there benefits to you being there to explain things?
Are there benefits in them knowing the information in question, or at least having witnessed something and possibly (most likely) not understanding it.
Do you have a plan for what to say when inevitable questions are asked? Can you guess the questions?
How long can a child stay in the dark on certain issues?
How does your child react to violence in general or graphic scenes? The likeliness of it being a traumatic event or easily accepted would vary from child to child.
Are you planning on discussing politics?
Are you taking a side, or offering third person perspective on the conflicts, explaining both sides' reasons for war, or just leaving it open as to why people do this?
How "street-smart" are you? Do you feel like you were too naive and wish you could have had some more practical real-life wisdom or awareness? Or the opposite? Do you wish you had more peace?
Is there a correlation between witnessing atrocities and unpleasant aspects of human nature and losing your childhood? What is the relationship?
Is the level of awareness inversely proportionate to innocence and youth?
Are there religious overtones that will need explained? ie, How could God let this happen? Does God not like those people? Who's side is God on? "Our [insert religious book] says it's wrong to hurt people and kill"
Do you practice or teach "Think for yourself, question everything"?
No matter what, she won't be able to UN-SEE whatever it is she sees. Thinking about these questions might help you to prepare and make a choice.
For what it's worth, I deal exposure to certain hardships as a form of keeping "Taking things for granted" in check. If a child is getting "spoiled" or having lots of expectations, history lessons and current events, as well as social studies are a good source of perspective of your actual situation. People certainly do use violence to acquire property on both a personal level and national level.
Knowing that people are suffering at all times somewhere on the planet is something everyone should be aware of to some extent, simply to be truly thankful for the times when things are good. One cannot fully appreciate where one is without fully understanding everywhere one isn't.
The bottom line:
This is an issue of timing and philosophy, and you know your child the best, as well as your parenting styles and choices. You know your beliefs on war, and if you want to raise your child to form their own beliefs or mirror yours until they form their own is purely your choice.