There was a little girl,
Who had a little curl,
Right in the middle of her forehead.
When she was good,
She was very good indeed,
But when she was bad she was horrid.
—Henry Wadsworth Longfellow
NAP (the libertarian Non-Aggression Principle) is not a moral principle. NAP is a social/political concept that has no practical application.
To any moral adult, NAP is an insult. Moral grown-ups do not need anyone to tell them, "look both ways before crossing the street," or, "never initiate the use of force against anyone."
Moral or ethical principles pertain only to individuals, and they are based on the requirements of human nature for successful living. For moral individuals, there really is no need for any other principles (e.g. political principles) because moral individuals are never a threat to any other individuals. All so called political principles are formulated on the assumption that most people in a society are not moral and are a potential threat to others. The whole purpose of NAP is to mitigate that potential threat; but NAP is not a means for controlling others—if it were, it would be immoral.
The purpose of ethics is not social. It is not others that determine what is right or wrong for an individual, it is what one's own nature requires one to do and not do if they are to live healthy, successful, happy lives.
In principle, if one lives a moral life and the consequence of that moral life were that the remainder of the entire human race suffered and perished, it would not diminish the virtue of the moral individual one iota. In reality, that consequence would be impossible because a moral individual is always productive and always interacts with others reasonably, and whatever influence a moral individual has on others is either neutral or benevolent. The benefit a moral life is to others, however, is never the purpose of ethics, it is the inevitable consequence of morals, not their purpose.
All ethical principles are for the benefit of, and only for the benefit of, those who live by them. NAP offers nothing of value to the individual who mistakenly believes NAP is a moral principle and attempts to guide his life by it. At best, "living by NAP," would evade one moral mistake, that of being a parasite using force to manipulate others. Otherwise, NAP provides absolutely nothing as a guide for living one's life, and it certainly won't make one successful, much less free.
Frequently associated with NAP is the idea of self-ownership and some libertarians, like Murray Rothbard, have even attempted to derive NAP from the self-ownership concept. The idea that one owns oneself, like a piece of property or their own slave, is preposterous, but there is a sense in which the idea might have meaning, but only if it means every individual has both total authority and total responsibility for their own life, and no individual has any authority or responsibility for anyone else's life.
There is an ethical basis for the principle that ties authority to responsibility. The obvious social application is not ethical, but political. The ethical aspect is derived from the fact that every individual has their own mind and must use it to learn all they can and think as well as they can, and to choose as judiciously as they can in order to live successfully. Every individual must make all their own choices, using their own ability to reason and their own knowledge to make them. It is not just the authority to make one's own choices, it is an absolute necessity that cannot be borrowed or passed off to anyone else. It is the first responsibility to do all one's own choosing. The second responsibility is the necessity to enjoy or bear the consequences of all one's own choices and actions.
One of the major problems for most individuals is the attempt to evade the responsibility for making one's own choices. They believe that one can evade the responsibility for the consequences of their choices by relying on someone else's authority, or expertise, or directions. How many people think they can excuse their worst actions by reciting the standard excuse, "I'm sorry, it's company policy," or, "it's the school's policy," or, "it's the community's decision," or even, "that's our tradition."
It is interesting that NAP does not address that kind of evil, because no one is "aggressing" against anyone, and that is horrid.