Read the (long) linked-to article from which the quote stems. Basically the point is that using violence to achieve a goal teaches the people involved that violence is an effective, legitimate way to achieve goals - and at some later point they will invariably have conflicting goals.

I'm not sure there's a useful distinction between those two options. Your future selves are part of the future world-states that it's exerting pressure on, and not exempt from that pressure.