Help me on "After The Genocide" by Philip Gourevitch rhetorical analysis

Hello:

I am doing a rhetorical anaylsis on "After the Genocide" by Philip Gourevitch. I am having problem to get the key idea about this essay and its purpose. I thought of it's an informative essay, and the author is trying to provide detailed, clear and accurate information on the changes of environment and people in Rwanda. It's a 700-1000 take home essay? Anybody can help me preceeding?