'If you want to be more than a victim of circumstances you're going to have to develop a capacity, and a willingness, to do harm.' Agree or disagree?

Depends on the circumstances, but broadly yes. It's obviously possible to do more than be a victim of circumstance w/o a willingness to hurt someone in some cases (i.e. a scientist who goes around discovering cool shit). But violence is, of course, appropriate in others, and yeah it can do that.