Were the Crusades justified?

On Facebook I responded to two critics of the Crusades:

Actually, I think the First Crusade was justified, to repel Muslim military invasion. However, the Crusades quickly went off the rails, and were ruthlessly conducted.

i) Although Urban II called upon the Franks to wage a counteroffensive against Muslim aggression, it's not as if "the church" led the military campaign. The pope, cardinals, bishops, and priests weren't combatants, although there was a military order of monks (Templars). 

All Urban II could do was urge the "civil ruling authorities" to repel Muslim invasion. Are you saying religious leaders should never give civilian leaders advice?

ii) Muslims were killing and enslaving Catholics. Didn't a medieval pope have a right to urge civilian authorities to protect Catholics? I'm not Catholic, but I'm just discussing the issue in terms of how the table was set in the middle ages.

iii) Where's the line between "the church" and civilians? Almost all civilians in the Western Roman empire were Catholic. 

iv) There is a tradition the men of the cloth should never take up arms. Do you agree with that? If a violent man storms into a Sunday school and threatens to kill the children, doesn't the pastor have duty to prevent a massacre by using lethal force, if necessary, to ward off the assailant? 

v) The appeal to Rom 13 is fallacious. To say civil authorities have a role in military action doesn't say anything about the role of the church one way or the other.

vi) There are multiple justifications given for the Crusades. We don't have to accept the justifications offered by Urban II to say the Crusades were justifiable in principle as an act of self-defense. We're not bound by Urban II's rationale. We can have independent reasons for believing it was necessary to repel Muslim military aggression.

vii) I agree with your larger point that Europeans make a basic mistake when they treat Roman Catholicism as their default representative of Christianity.

i) You're not listening. The "church" didn't wage war. Pope Urban II urged civil authorities to organize a counteroffensive to Muslim invasion.  

ii) Are you a pacifist? There's nothing wrong with taking life per se. There's an elementary distinction between taking innocent lives and killing assailants to protect innocent life.

There are also situations in which taking innocent life is a tragic necessity, viz. human shield situations.

Your first statement was a inarticulate endorsement of "Christian" jihad.

My first statement was no such thing. My first statement was "I think the First Crusade was justified, to repel Muslim military invasion."

That's hardly equivalent to "Christian jihad". Jihad is the principle of forcible mass conversion by military conquest and subjugation. Take Ibn Khaldun statement that: "In the Muslim community, the holy war is a religious duty, because of the universalism of the Muslim mission and (the obligation to) convert everybody to Islam either by persuasion or by force...It is (for them to choose between) conversion to Islam, payment of the poll tax, or death" (Muqaddimah, chapter 3.31). 

A counteroffensive against Muslim military invasion is by no means equivalent to that principle. Rather, it's simply self-defense. 

Loss of innocent life is what provokes the natural man to feel justified in waging war.

That's historically naive. Wars of aggression are frequently motivated by wanting something another tribe or country has, such as natural resources. Raiding parties to loot and plunder. They aren't motivated by retaliation for the loss of innocent life on their side. 

So that means that if you practice offensive war strategies, you give your enemy justification to likewise wage a counter-offensive against you until death & destruction is satisfied between the two.

That's a false equivalence because it fails to take just cause into account. Your objection is morally simplistic. 

That said, I am firmly convinced that the business of war is the business of ruling authorities and not the church.

Yes, you keep reciting your flashcard slogans, but I already discussed the ambiguities of that claim. Put down the flashcards and try interacting with the actual argument, if you can.

Just to be systematic, let's untangle your confusions:

Military action is not justified by the church - it is a function of civil ruling authority (Matthew 26:52, Romans 13:4, Romans 13:11). The only sword The Body of Christ is commanded to carry is the The Word (Ephesians 6:17).

i) As I said before, I'm not Roman Catholic. I'm not sympathetic to Roman Catholicism. Therefore, I don't consider the pope to be a spokesman for or representative of the church. No doubt he symbolizes the "church" in the eyes of many people. 

ii) You overgeneralize from Mt 26:52. When Peter tries to prevent the arrest of Jesus, he reveals his failure to understand when Jesus came in the first place. Jesus had a unique mission.

But you yourself concede the right of self-defense. So the passage is irrelevant to the issue at hand.

iii) Rom 13 isn't framed as a comparative statement. It doesn't say these are the duties of the state in opposition to the church. It doesn't address the church one way or the other. It doesn't set the duties of the state in contrast to the duties of the church. As far as Rom 13 goes, church and state might have some overlapping prerogatives. The text is neutral on that question. For instance, to say police have the authority to make an arrest doesn't imply that FBI agents don't have the authority to make an arrest. 

iv) You never bother to define "the church". Does "the church" include the laity? If so, you admit that you believe in the right of self-defense. If so, then when Christians participate in a defensive war, that's the church waging war. If "the church" is the people of God, then when Christians exercise the right of self-defense, that's the church acting. So your usage is equivocal.

v) Perhaps, though, you are using "the church" in a more restrictive sense to mean ecclesiastical leaders like the pope. But the Crusaders weren't papal draftees. He didn't have the power to conscript the Franks to fight in the Crusades. It was a volunteer army. 

Likewise, the war wasn't prosecuted by the papacy. Priests, bishops, and cardinals weren't combatants. So, once again, your usage is equivocal. 

vi) You apparently concede that there's nothing wrong in principle with ecclesiastical leaders given political leaders advice. 

vii) It's unclear how your appeal to Eph 6:17 is consistent with your admission regarding self-defense. If you believe Christians are entitled to practice self-defense, then that's not confined to a spiritual sword, but actual weapons.

My apologies if you thought I was arguing that wars are legitimately waged on the basis of the loss of innocent life. That was not my argument at all. I was arguing that if your moral justification for waging war is to protect innocent life for your own while acknowledging that a counter-offensive will generate 'necessary loss of innocent life' for your enemy, then by your own moral standards, you are providing 'just' cause for your enemy to also launch a counter-offensive in response to your counter-offensive which is a downward moral loop of revenge. 

That doesn't follow from my own moral standards because the moral considerations are more complex than that. If country A launches an unprovoked attack on country B, and if the aggressor locates military assets (e.g. military manufacturing) in civilian population centers, it may be impossible for country B to effective defend itself without downgrading the military capacity of the aggressor by counterattacking civilian population centers where military assets are situated. That doesn't justify a "moral loop of revenge" because, among other things, this is not about revenge but national defense in response to an unprovoked attack. Who initiates the aggression is a morally salient factor. Likewise, if the aggressor makes it impossible for the other country to protect itself without inflicting civilian casualties as a regrettable but unavoidable side-effect of justified self-defense, that's exculpatory. 

I am not using a flashcard slogan when I say war is the business of the state & not the church - I am using the Bible which I cited in my very first statement. So if you don't like that idea, you should be directing your condescending shame at God's Word for being a flashcard.

The inferences you draw from Scripture are not the same as Scripture itself. Anyone can quote Scripture. 

Matthew 26:52 is not irrelevant as it concerning a preemptive counter-offensive act & not a defensive act.

i) You're acting like that inculcates a general principle, which disregards the context. For one thing, Jesus didn't need anyone to protect himself. He had the omnipotent power to defend himself, if he wanted to.

ii) And attempting to thwart his arrest would thwart the purpose of his mission. 

iii) The First Crusade was not a "preemptive counteroffensive", but a belated response to multiple Muslim incursions and depredations. It was long overdue. 

iv) It's artificial to posit a dichotomy in principle between self-defense and preemption. If, say, a suicide bomber with a conspicuous shahid jacket is headed into a synagogue, it is morally permissible, indeed morally obligatory, for armed guards to shoot him dead before he enters the synagogue and denotes the vest. 

I agree that the church is not a denomination & certainly not 1 person such as a pope. Your initial statement in context was a moral endorsement of church waging a military offensive (whether you meant the pope, :the church" or genuine believers directly or indirectly was not articulated).

i) No, that is you recasting what I said into your own categories, which I reject. 

ii) I didn't say military "offensive" but "counteroffensive". The difference is significant.

iii) Is it your position that when Christians are participants in war, that's tantamount to "the church" waging war? 

That really isn't the issue from my perspective as much as the difference between a defensive act to preserve one's own life vs. an offensive act to take someone's life -- some of whom you acknowledged are totally innocent.

That's a false dichotomy. Take the suicide bomber example (see above). That's not a defensive act to preserve one's own life. And that's not an "offensive" act to take someone else's life. Rather, that's a defensive act to protect the innocent lives of a second parties.