I wonder if you would say the same on the other side where every male or female above 18 years is required to serve in thr military and in the reserve afterwards? [1]
By your argument would you say that all of these are legitimate targets?
I don't think anything in the grandparent post suggested that. If someone used to be a combatant and then ceased fighting, usually they then become a civilian. They don't stay a combatant for life. Reserve forces not on duty are not generally combatants. You have to be in the fight to be a combatant.
Things get more complicated with combatants who don't fully wear uniforms, which is why failing to wear a uniform is a war crime.
It should be noted this isn't so much the grandparent's personal opinion as they are just paraphrasing what the geneva convention says. However there is of course a lot more details to it then that and the devil is in the details.
[Edit: i think i read the post too quickly. The grandparent is incorrect when saying "[Civilians] also includes members of the civil population who are actually involved in hostilities without being a formal part of an armed force.". If you pick up a gun and start shooting the other side, you are not a civilian. It doesn't matter whether you are formally part of the armed forces. Civilians get protected because we want to protect the innocents stuck in the middle. People who are taking part in a war dont get that protection]
You're not a civilian while you're holding the gun, but you are once you stop shooting again: you lose your protection as a civilian during your period of direct participation. Should have been more clear on that.
It's probably also worth saying that -- while there's a degree of subtlety and complexity when considering the legal and moral position of Israel's armed forces -- there's very little to debate when it comes to actions like the Re'im music festival attack. That kind of action is obviously illegal and morally repugnant.
No, there is no such complexity. There are very obviously undebatable incidents of war crimes by the IDF. Like this footage from a drone who deliberately killed civilians in plain sight and trying to cover the bodies[1] and the IDF targeting aid workers in a location they knew about [2]. Also, there are widespread videos by IDF soldiers committing atrocities and crimes in Gaza and posting it on social media. That is hardly self-defense. This is obvious war crimes against civilians. Not to mention the mass starvation and carpet bombing of civilians. There is very little to debate, and denying them is immoral. You are just using a very old tactic of trying to minimize IDF crimes by claiming their position is complex. Remember the old say "Middle East is complex mess, let's just ignore what is happening there"
[1] https://www.aljazeera.com/program/newsfeed/2024/3/22/gaza-dr...
[2] https://www.cbsnews.com/news/central-world-kitchen-aid-worke...
Some of the other things you mention have a lot of grey area, because whether or not they are a war crime don't necessarily depend solely on what happened, but on what Israel's intent was and what they knew at various points in time. Which is information that's hard to know from our vantage point. Some of them could be, but there is also potential that they might not be. Its not as clear cut as you make it out to be.
I don't think these things are as unequivocal as you suggest. I mean, you're assuming those people are civilians. Maybe they're not. Almost certainly we will never know for sure, and if you can't acknowledge that then you're not being objective.
I am not your parent commenter, and do not necessarily subscribe to any of their arguments, but I can answer your question directly: yes, to some people, the conscription of all people in a certain age range does make them legitimate targets.
In particular, from my perspective, one of the primary downsides of the inclusion of women in the armed forces is specifically that it legitimizes taegetting (other) women as a military target.
So, to be explicit, if an organization I conscripts women into their military and someone else targets I women militarily, then I will hold I morally responsible for their fate. Similarly, if an organization H utilizes children as soldiers (or human shields) and other children are militarily targeted, I will consider H morally responsible for their fate. (And to be more explicit still: sucks for all the men everywhere.)