In A Just War in a Time of Terrorism: A Franciscan Perspective, David B. Couturier, OFM. Cap (
fi-na.org/page1.html)
considers the Just War criteria.
On the criteria that one wages war in order to establish peace he says this~ War must be waged with peace as the end in mind. War is not a moral good; it is, at best, a necessary evil.
Obviously it is just his opinion but surely peace and war cannot both be moral goods can they?
Parenthetically he also says~ As I stated earlier, the principles used to justify going to war are integral. If any of these requirements are missing or not in evidence, then the war is not considered just. Also, if there is evidence to the contrary that indicates that one of these principles is not fulfilled, then the war is not considered just. So, if it can be proven that the motivation for war is not peace but expansion or access to resources, (ie. more water or more oil), then the war cannot be claimed as just.
There is also an interesting consideration of the question @
sspx.org/against_the_sound_bites/just_war.htm
“War is still a physical evil, with suffering and loss, and, at the same time, the cause of moral evils which will perhaps accidentally follow —souls will be called before the judgment seat of God without being prepared, or called in the drunkenness of massacre, or in the hatred for the enemy. As such, war is a consequence of original sin, a feature of our present fallen state.”
" Nevertheless, even for the Christian there exists the danger of exalting war as such, as it is willed and carried on by men. War as such is always a disaster and a crime, at least materially and at least on one of the belligerent sides."
"
Finally, there is the objection which is foremost in most minds: the indisputable horror and cruelty of war. How is it possible to ensure that the disorder and suffering caused by the war will not fly out of control and thereby lose all proportion to the original offense? War will always entail the incalculable loss of human lives, moral and material disasters —and these upon people who, for the most part, do not have direct responsibility for the infliction of the original injury. How firm is the hope that, following such suffering, justice, order, and peace will be restored? This danger, which has been present as long as men have been on earth, has increased exponentially by scientific and technological developments in military hardware. Add to this that the solidarity among nations today almost invariably extends military conflicts to several nations, and one sees that evil consequences may indirectly affect generations to come.
Many modern theologians consider that today there is no morally admissible hypothesis by which a state could resort to war. John XXIII accepted this position in his encyclical
Pacem in Terris: *“In this age which boasts of its atomic power, it no longer makes sense to maintain that war is a fit instrument with which to repair the violation of justice.”
*
The theory that the outcome of war can be a moral good does not necessarily mean that the war itself is a moral good. Not least because the course and outcome of the war cannot be foretold with certainty by any of the persons involved in it.
