What's a world tradgedy (like columbine, holocaust, rowanda...etc)?

I have to write an allegory(like a short story symbolizing something. ie bunnies would represent the jews and the humans representing Nazis would take them away from the forest. representing the Holocaust) on a world atrocity that has happened. It has to be in my lifetime though. So anything from 1993 onward would be good :D. Thanks ^_^