Seth, yes restitution/retribution will have to take place (a competitive legal system would define what's just), but the NAP hasn't been broken, because in order to break it the harm you do must be intentional. The NAP does not solve these kinds of situations, a competitive market in law and arbitration does.

The NAP is not a magic pill that will solve all our problems, but chances are a free market will.

The correct answer is no. Aggression implies intention. Strictly speaking, the NAP does not solve these kinds of situations. A competitive court and arbitration market does.

That being said, Seth is correct stating that "people are ethically response for their actions, accident or otherwise." That conclusion doesn't stem from the NAP though, it's just common sense ethics, with some exceptions.

http://www.youtube.com/watch?v=AMSMQHpIEQU