What is the role of the Taliban and how does Hosseini portray it?

The Taliban took over as the Russians left. They are portrayed as ruthless people bent on enforcing a narrow interpretation of the Koran. The Taliban are portrayed as being responsible for unspeakable tragedies (rape, murder....) through the story. You can check out more on the background below.

http://www.gradesaver.com/the-kite-runner/study-guide/section9/