For many thousands of years, the underlying principle of civilization has been "might makes right". The governments in it codify their laws such that the government itself becomes the regional monopoly on the justified use of force. Within the past few centuries, civilization has slowly been moving towards "the ends justify the means". While that is slightly better, as a fundamental organizing principle of civilization, it is still not ideal, in my opinion.
For now, civilization largely consists of a mutual compact regarding when it is morally acceptable to employ violence. In exchange for obeying the rules, we are promised some of the benefits resulting from collectively standing down from a state of universal hypervigilance.
A hungry and homeless person may perceive that he or she is not getting their fair share of society's mutual benefits. Civilization has not honored its end of the bargain, so they need not honor theirs. There is no moral reason for them to restrain themselves from committing any act considered a crime by civilization. They may still choose to remain within the law, for practical reasons, but it would not be because they are morally obligated to do so. They could rebel at any time. Many do not, and never will.
Consider that if no one ever went outlaw, civilization would have little incentive to give its underclass anything. If you only need a million warm bodies to run the machines, you dump 3 Mcal down the feed chutes every day, and let the rabble argue among themselves over who gets to eat it. If no one is willing to fight the system, everyone is safe to ignore.
Civilization would serve itself best by ensuring that its bounty is distributed evenly enough such that those at the bottom perceive that they would have something significant to lose by rebelling. Though it may also preemptively defend itself against such people by ensuring that they cannot present a significant criminal or military threat if they do turn. You can build shelters and bread lines, or you can build prisons and walls. Not coincidentally, those are the typical strategies of parties considered "left" or "right" politically, worldwide.
If it truly is a last resort, a human with nothing is not ethically restrained in any way from doing anything at all. It might be breaking your car window and stealing something out of your back seat. It might be beating you to death and eating your liver. It might be to give you the sad, puppy-dog eyes, shake some change in a coffee cup, and sing the blues. A civilization that provides no benefits cannot reasonably expect conduct different from the savage, naked savannah-ape in the wild. They don't always kill each other, but they certainly don't worry about laws when they do.
A few in recent history have been moderately wealthy, but their poverty lies not in the economic but rather sexual market. Society has denied their right to reproduce, and did not arrange a marriage for them which could have prevented their killing spree. Were they morally justified to harm others?
You are saying that gives them a license to kill. Society denied them something, so you are saying that a justifiable response is to lash out at others. You see there is no point negotiating with people like that, that's when violence is justified.
If you choose to enslave someone, you can never trust them to not rise up and murder you in your sleep. There is always the chance that they will think it through and reach the morally correct (for them) course of action--to kill the slave-owner. So logically, if you don't want to be murdered in your sleep, you can either abolish slavery, or you can lock all the slaves up every night. Either one of those strategies would work. In different eras, both have been considered the ethically correct action.
The morally correct response for someone denied reproductive freedom by, for instance, laws supporting polygamy, is to break the laws abolishing adultery. If one man has four wives, there will generally be three other men who shouldn't really consider marital fidelity to be all that important. Or maybe some of them won't consider strict heterosexuality to be a culturally critical ideal.
And if that particular society further undermines those men--perhaps by vigorously defending the wives and daughters, and beheading the ones seeking alternate arrangements--they would be morally justified in committing violence against the people and institutions who denied them those benefits of having a civilized society. It is by no means guaranteed that such people will be able to precisely or accurately identify the "correct" people or institutions. They are right to lash out. They are getting shafted by an unfair system, after all, and that system is unlikely to change for their benefit if they continue to passively support it.
As such, it is also morally justified for other societies, recognizing that violent and possibly ignorant potential, to either proactively defend themselves against it, or to deflect the violence towards alternate targets. It is therefore possible for multiple sides of a violent and bloody conflict to all be acting in a manner that they consider to be morally correct.
It would be better for everyone, all around, if civilization did not choose to stratify itself such that a permanent underclass exists. If fewer people were treated unfairly, fewer people would lash out against the unfairness. As the violence is itself usually applied unfairly, unfairness begets unfairness, injustice breeds injustice, vengeance calls for more vengeance.
If you don't want unending spirals of oppression and rebellion, you have to take proactive measures to peacefully increase the perception of fairness in society. There are many ways to accomplish that. If you don't want peaceful, civilized people to wind up dead because there were too many people that saw no benefit from being peaceful and civilized, you should be pushing to bring more benefits of civilization to more people. Or you should be exterminating the "uncivilized" people. Either way. I personally consider one of those to be ethically abhorrent, but civilization as a whole still seems to be on the fence about it.
>It is therefore possible for multiple sides of a violent and bloody conflict to all be acting in a manner that they consider to be morally correct.
So violence is always correct when I do it, but not when my opponent does it against me, right? What an infantile way of thinking.
>It would be better for everyone, all around, if civilization did not choose to stratify itself such that a permanent underclass exists.
Sounds like you believe in a utopian ideal of a classless society.
To me it's just empty words you are saying, you won't take risks for your ideals, like every other middle-class ideological leftist. Move to a low-income neighborhood, experience first-hand what a robbery feels like, or to be on the business end of a gun. Remember that the Red Guard were the first to be executed.
