This is true. There are, however, much broader, and much more difficult, questions that no one wants to engage with, probably because there are no answers that will make anyone happy.
Those questions surround the very concept of “legal” or “just” war, and the rules we create to manage conflict. At the most direct, worm’s-eye level, there is no just or unjust killing, it’s all killing. Dead is dead. Long ago, though, people from a wide variety of cultures recognized that without some sort of accepted limits, things would get way out of hand. So traditions, agreements, social norms, rules, laws, whatever were hashed out–between relatively similar societies.
Later, in some societies including Christian Europe, the idea of a “just war,” or a conflict allowed or perhaps even sanctioned by God emerged, along with some often elaborate and elegant theological and philosophical arguments. Of course, given that each combatant would always make the argument that their side was just, you needed a neutral third-party with the knowledge to adjudicate these things, and the authority to make it stick. While the Church claimed that authority, it was too often a party to the very disputes it sought to arbitrate (and when non-Christians were involved, it was perhaps the worst arbiter, though no one in Europe really cared, given that by then Europe = Christian and everyone else could literally go to Hell).
The colonial and imperial ages saw warfare increasingly shift from constant fighting among European states to constant fighting between European states and non-Europeans whose lands and resources the Europeans coveted. The same pattern we see today emerged often immediately, as regards “just” wars. Europeans universally declared violence by the colonized against Europeans unjust, criminal, terroristic, etc. while massacring the locals with Maxim guns was deemed good Christian chastisement of the heathen as it were. As the threat of intra-European war still loomed–as WWI would make manifest–a need still existed to codify how advanced nations might duke it out, so as to guard against the unlikely but unpleasant possibility of a white army treating another white army the way they treated the Sudanese or Hottentots or Chinese. Thus the succession of agreements that would over the decades into the 20th century become the so-called Geneva Conventions and related things.
These agreements were still rooted mostly in the colonial mindset. Every colonial power needed a way to insure that no colonized peoples could be mistaken for a legitimate army or government, and that Europeans maintained a monopoly on the use of force. As they knew that was utterly impossible, they went for the next best thing, defining “legitimate” war as all the things that an irregular, guerilla, anti-colonial, or otherwise non-industrial, non-advanced (and, um, not white) people might have to resort to to inflict damage on and sway the policies of a colonizing, modern (and, um, white) power.
Ever since then, any sort of asymmetrical warfare has tossed up the same problem. The definitions of “just” and allowed violence are so rooted in one particular type of warfare, and one particular type of warfighting apparatus, that it is virtually impossible for any military force other than those from advanced industrialized societies to adhere to them and retain any semblance of effectiveness. Almost all fighting today is asymmetric, and many conflicts involve struggles against Western or Western-affiliated states. Yet virtually every act of war that is feasible for the weaker sides, and which might actually have a chance to effect the political change that war is intended to effect, is outlawed by the so-called laws of war.
What might have worked when advanced industrial society fought its doppelganger (and even then I’d argue hypocrisy was more the norm too, with might always making right) simply does not work in asymmetrical post-modern warfare.
Note I am not saying it is “good” to bomb hospitals, set up shop using civilians as shields, blow up grocery stores, fire rockets at apartments, whatever. A country like Israel facing such attacks, at the basic, ground level, is going to have to respond to them. And certainly as an individual I find the notion of such attacks repulsive. Talking at a higher level, though, getting beyond the adrenaline-fueled, go-go-go! tactical chaos, what we have is a fundamental inequity and a self-perpetuating problem. We are in effect saying, “no one can fight any war, or use violence in any way, unless they can do so according to the rules we wrote, and which only an advanced, modern military can adhere to, much less win with.” And of course as we fudge our own rules constantly, we being the West in general as no one else really squawks much about this stuff, our moral authority is less than compelling.
The original concept of the just war was a high-level moral and religious idea, fundamentally built around the ultimate goal of the conflict. All things being equal, the side with the “best,” or most ethically or morally supported cause, was the “just” side. We have reduced that to a very cynical means test that lets highly advanced military powers do anything they want and labels virtually everything else a war crime. In the process, we skipped over the whole interrogation of the causes and goals of war, instead focusing only and solely on the minutia of which bomb went where and whether the victims wore a specific uniform or not.
tl;dr, the real question is not “should Israel have bombed this apartment building,” or even “should Hamas have lobbed rockets at Israel.” The real question is, “which side has the best argument for violence in the first place?” And that discussion has to take into account not only the low-level (response to immediate provocation) but the high level (creating the conditions that generate the provocations).
