...that adherende to the nonagression principle is a sufficient condition for libertarianism, narrowly defined.

But treating other badly for race or gender reasons, taking advantage of one's authority in a hierarchy to push other people around, etc.--while not formally inconsistent with the NAP--is still at odds with the cultural and personality traits that attract most people to libertarianism.

As Charles Johnson said, one can be a consistent libertarian by adhering to the nonaggression principle and simultaneously supporting voluntary racist and authoritarian behavior--but it's *weird*. It's the kind of behavior that would naturally lead someone to wonder, "why's he even a libertarian, anyway?" The kinds of people who like turning Hispanics or Chinese away from their business establishments don't generally have the personality types that lead people to embrace the nonaggression principle.