Strategic behavior can be irrational insofar as it deviates from rational and sustainable behavior depending on the environment and teleology of events. It would be silly to blame a person in an irrational environment for behaving strategically, since that person couldn’t survive any other way. Likewise strategic behavior in a rational environment is more egregious but people seem to be able to get away with it by making certain emotional appeals and throwing histrionic fits.
In the Harry Potter movie, Harry behaves strategically and uses his magick and irrational act, in a rational environment, but he is provoked by a Dementor attacking himself and his relative. So, teleologically speaking he behaved irrationally in a rational environment after being provoked by an irrational action, why is this ok?
Jus ad bellum
Just cause/ Right intention
According to the principle of right intention, the aim of war must not be to pursue narrowly defined national interests, but rather to re-establish a just peace. This state of peace should be preferable to the conditions that would have prevailed had the war not occurred.
The principle of proportionality stipulates that the violence used in the war must be proportional to the attack suffered. For example, if one nation invades and seizes the land of another nation, this second nation has just cause for a counterattack in order to retrieve its land. However, if this second nation invades the first, reclaims its territory, and then also annexes the first nation, such military action is disproportional.
The principle of last resort stipulates that all non-violent options must first be exhausted before the use of force can be justified.
What is interesting with people and their judgments nowadays, is that people respond with horror when a rational person defends themselves against an irrational person that is forcing a confrontation, as if there is a virtue in letting psychopaths force their will on everybody and get away with it. This just emboldens them to do it again in the future.
Contemplate if you will, the rules governing gun play in the cowboy days, shooting an unarmed man was an act of murder, but shooting an armed man was acceptable because shit happens. Now what is interesting is that today you have psychopathic structures of authority in relationship with protecting and expanding their authority, and they have an incentive in a situation where the rational person defends himself and wins, to fly in the face of reason and rule against the righteous person defending themselves against the lawless, irrational man.