I have an opinion I'd like some feedback on. My view on war is generally that it's a bad idea. Aggression against another country or similar entity is difficult to justify.
However the fact remains that an outside force can invade and make war on your country. My opinion on this is that an invader should be destroyed completely. Ruthless exploitation of any weakness, and use of any weapon is completely justified to expel the threat, at least until they have ceased their aggression and given back any territory gained. After that it would be difficult again to justify continuing the use of ruthless tactics in an act of aggression towards your enemy in their own territory.
My idea of using complete force against an aggressor comes from that you didn't make war on them. They brought war to you.
For example, if you were being violently mugged, it would be justified to kill your assailant. However, it would be unjustified to go out and kill someone just because they might mug you. Or, if you were mugged and you used force to defend yourself and did so successfully, but the mugger escaped, it would be unjustified to seek them out and kill them, since there is no longer the threat of being mugged by them.
What do you think on this?