It is imperative for an artist to be honest, to respect the creative impulse, wherever that may go. Anything less is just decoration or inconsequential humming. Sometimes the resulting art is repugnant, but I believe the world is better for it, that it is made richer by having those thoughts explored. Essentially any theme or subject could trigger memory of trauma depending on the context.
The reason we value art is its ability to move people, its ability to be larger than itself and engender a greater experience, an experience that can inform an entire lifetime. In some cases that greater experience is unpleasant or insulting, but it is there.
-Steve Albini, in Listen
