It’s amazing how many libertarians and libertarian adjacent people don’t understand that people don’t process information the same way at a fundamental level. This means that even people who use the NAP to govern their actions will not interpret the NAP the same way in a given situation. So yes. Both sides in a conflict can actually think the other side violated the NAP on them and they are acting in self defense. Both sides. At the same. The chaser? You probably aren’t changing most people’s minds about their interpretation. Especially if their wellbeing is tied to their interpretation.
Nothing stopping you from defending yourself in any situation of course but when you and yours have to bear all the costs win, lose or draw against them and theirs, I hope it was worth it. Especially if your talking about a group local to you. The reality is if someone decides to end you and isn’t a complete moron about it you are done. It’s a rifle shot from 300 yards. Its a ball peen hammer to the back of the skull while you are walking down the street. Don’t forget that the family of the person you self defensed is still in the area and their response will be governed by their interpretation of events. We lose sight of that several generations into a society where the government has power enough to put the kybosh on most of that and people being used to using the state to handle disputes with one another and retaliating for wrongs.