We try not to defend ourselves from our enemies or we try not to harm them if we do.
When a disciple finds themself in a situation where force is the only way to help another innocent person, we seek to use as little force as possible and try not to harm someone when seeking to help the innocent person.
We do not take up arms for a world's nation since we don't belong to the nations or their leaders and we will not be used as murderous pawns in unjust initiated aggressions.
We know that violence will at best only solve a temporary situation and solve it in an inferior manner, and the ramification of using violence will likely cause more hate, animosity and violence and thus encourage continuing the cycle.
Perhaps the largest problem with understanding this issue is that people do not see the two kingdoms. There is the kingdom of God and there are the kingdoms of men. Disciples have entered into the kingdom of God and thus have left the kingdoms of men.
"If you were of the world, the world would love its own; but because you are not of the world, but I chose you out of the world, because of this the world hates you." John 15:18
"Jesus answered, “My kingdom is not of this world. If My kingdom were of this world, then My servants would be fighting so that I would not be handed over to the Jews; but as it is, My kingdom is not of this realm.” John 18:36
Obviously this does not mean we leave the earth, but it DOES mean that we no longer have allegiances to the rulers of this world. Stated another way, we look with our faith to our King as our Leader and not men or women. We comply with the rules/laws of men where we live unless those rules/laws go against our King. This view solves the confusion of entering into the world's militaries. We do not join the armies of the world to fight their battles and their nation's/kingdom's enemies. We do not listen to political rulers who choose an enemy normally based on unrighteous reasons, and to take their weapons and use them to kill people we don't even know. Again, "our enemies" in Joshua's saying "love your enemies" does NOT represent nameless, faceless people of another nation that a government calls their enemy and wants us to kill. Rather, those who choose to make themselves our enemies are those who know us to some degree and they have chosen to make themselves our enemies based on unrighteous reasons.
Let us clarify another important aspect of this issue. Let us take a look at a few saying of The Light in this context:
“You have heard that it was said, ‘An eye for an eye, and a tooth for a tooth.’ But I say to you, do not resist an evil person; but whoever slaps you on your right cheek, turn the other to him also. If anyone wants to sue you and take your shirt, let him have your coat also." Matt. 5:39-40
"...bless those who curse you, pray for those who mistreat you. Whoever hits you on the cheek, offer him the other also; and whoever takes away your coat, do not withhold your shirt from him either. Give to everyone who asks of you, and whoever takes away what is yours, do not demand it back." Luke 6:29-30
The sayings above are clearly dealing with individual situations where you know the person to some degree, or where the person/enemy is not trying to seriously hurt you but rather insulting you or trying to take something from your, e.g. "slaps" and "sue you" or "take away". Joshua's saying are not language describing a murderous or violently predisposed person willing to hurt your or kill you to get something. Therefore, we can conclude that Joshua is not addressing defending your physical well being in those passages, but rather our self-pride or our material things. In this case, giving the person what they want to forcefully take from us is a form of loving our enemy. If they really need that shirt or coat, give it to them. If they really need to spit on us, let them do so. Find compassion for the current state of their soul which is causing them to do wrong. Again, when Joshua says, "love your enemies", there is the assumption that those people know us to some degree, and thus our love towards them can be a very effective way to show them our Father.
Now, regarding those who want to do violence against us or those around us. Our enemies are those who choose to make themselves such towards us since disciples don't have animosity towards others. As disciples of The Light, we do not initiate violence towards others...we do not use force to get our way. If we are attacked, we can defend ourselves but we would do so without malice or animosity towards our attacker, and thus we would seek to use minimal force so as not to unduly harm them. We turn the other cheek to those who taunt us and seek to bring us into violence...we walk away.
Some wonder what we should do about groups like Boko Haram or ISIS or other such murderous groups. This perspective is similar to the world's militaries issue above. As disciples, we live our life out where we are. We don't travel the earth seeking to use violence to solve violence. We do not join the world's organizations because we cannot trust that they are doing things the right way or for the right motivation. If we have a chance to make peace between two people groups, then we do so. If we live near or among people who are being attacked by groups like Boko Haram, the principles already discussed address that...we seek to defend the innocent through non-violent means or to use as little force as possible to do so.
What we do not do as disciples is act as cowards, meaning we would not defend the innocent or weak when we find ourselves in a normal daily life situation where the innocent or weak need help or protection. What we do not do is get caught up in self-pride or fear and go into evil fits of murderous rage towards others and call that somehow being 'brave' or 'courageous'.
True courage is standing up to people we know who want to do what is wrong and being hated or rejected as a result. False courage or misplaced courage is taking up a weapon and killing people you don't even know are guilty of any wrongdoing except being labeled as "your enemy" by the government of the nation you live in.
Finally, what if a Family of disciples is attacked where they are? It would depend upon the reason. If it is persecution from the people of the place/area/nation where we live, then we should flee to another place as Joshua instructs.
"But whenever they persecute you in one city, flee to the next..." Matt. 10:23
If it is something like one nation taking over another nation and we are merely in the crosshairs of that larger conflict, and those people come to kill us just because we are seen as being part of the nation where we reside, we could defend our women and children from them or we could flee depending upon the specifics of the situation.
What is most important, is that we spend out time spreading and living out the Solution to mankind's conflict problems...we bring The Peacemaker to others and show the world the better way of his love and truth and rightness.
Please come into Life and join the Peaceful Revolution!