How is the history of genocide important or relevant to philosophy?

There are two main ways in which genocide is important to
the study of philosophy.

First, there is what is called the
"problem of evil."  This is the question of whether the existence of evil calls into
question the existence of God -- if evil exists can an all powerful and good God also
exist?  Genocide is perhaps the ultimate evil that people do and therefore impacts on
this issue.

Second, there is the problem of what philosophy
can or cannot do to end genocide.  There have been philosophical approaches that have
tried to combat genocide, but there have also been philosophical schools of thought
whose teachings have helped lead to genocide.  Therefore, it is important to philosophy
to ask what, if anything, philosophy as a discipline can do to end
genocide.