18-year-olds have been volunteer recruited and drafted for perhaps the entire history of organized armies. Child soldiers also have (and in some countries still are) enlisted also. I suspect this is only out of extreme necessity, as the moral and practical drawbacks are overwhelming.
When the United States has instituted the draft, it has encompassed 18-to-45 year-olds for immediate enlistment. 18-25 year-olds comprise the largest age group of new volunteer enlistees in the US. The largest barriers to military service qualification are health reasons and family situations. It would follow that younger enlistees would have lower likelihood of physical injuries and being the sole caretaker of a dependent.
Your post made sense until your bizarre digression to armed service being linked to incomplete prefrontal cortex development. It can be appealing to find sinister motivations behind institutions you dislike, but there isn't a basis in fact here. The explanation is tradition, health, and lack of obligations.
Ignoring that reality, and why 12 year olds are more likely to pick up a machete than a 30 year old, is what's bizarre.
Recruitment of child soldiers usually involves drugging the targets. 12 year olds are probably less susceptible to be able to realize that they're being drugged and to have the mental fortitude to retain their self through the grooming process. I suspect that even when drugged, a 30 year old will have a better sense of being drugged and is less likely to be brainwashed. There are also other shock-inducing factors that have a greater dislocating impact on 12 year olds, such as killing their parents (both it happening in front of them, and/or in some cases, them being forced to do it as part of the indoctrination process). I suspect that a 30 year old would be more likely to channel their anger at the "recruiter" than a 12 year old would.
Also kids are easily guided to do just about anything. They're easily impressed and even the brightest lack the experience to temper their judgement of what is a good idea versus what isn't.
Are there any sources, papers or studies indicating whether it is learned, innate or both?
Sources and empiricism are what we should be resorting to, not down-votes.
I want to know why the people going back and forth think one way or the other. If I rely on my own research I might not get the nuance that a psychologist or other person with a vested interest would be able to share.
There seems a great deal smoke but no light in this discussion. This is uncommon here on hacker news, normally sources are appreciated and I frequently see them brought in well before an argument begins, even on extremely casual topics. They often earn an few upvotes too.
So again, if you want to add to the discussion, add to it, don't try to control it.
At the moment there is no reason to believe either side and plenty of reasons to dismiss both, not as cranks, but at least as cranky.
Complaining on a form inherently lowers it's quality. As a rule Down-vote, Flag, or say nothing don't clutter up HN with posts that make for poor reading.
And yes, mass downvoting both sides of a thread is often better than getting in the middle of a heated debate.
Lets not pretend that it is.
As well as dogs. Dogs have empathy, even for humans.
So yeah, the idea that an 18 year old is struggling with an emotion that babies and dogs don't have much trouble with is a silly proclamation IMO.
Most of the reading I've done seems to suggest that that's something that's developed at a very young age, and very sensitive to early childhood environment, rather something people are born with.
There's a reason that everyone, for better or worse, wants to get to kids early, and often. Advertisers, religions, people trying to teach kids how to deal with advertisers and religions, militaries, etc... all see the value in "getting them young."
I get that this is a dissociative POV.
So often these discussions are about youthful feelings of immortality, more courage, foolishness, etc., but that never rang true personally.
No no. Prefrontal cortex development. Who needs an entirely plausible rational explanation when you can point to mysterious and poorly understood brain-physical reasons?
They are also approaching peak physical fitness, both as to capacity for difficult physical work, and to the ability to recover from severe trauma.
[Edit: one should probably not exaggerate the idealism of draftees. Maybe it was there in WW I, but the accounts of WW II and since suggest that it fell off.]
Physical fitness surely? Isn't 18 or 19 around the physical fitness peak? I'm guessing that people are on average are significantly stronger and more robust at 18 than they are at 28. I think the British Army has 26 as the limit for joining in the first place for officers at least.
Also people are married by 28. At 18 they're generally single and more able to deploy.
You may have a point about average fitness and rate of improvement, though.
One of the advantages (and disadvantages) of sending 18-20 year olds into battlefield is that if they die society spent less money/effort into teaching them some other valuable skill that would have been lost without getting the benefit out of it (due to the person being dead)
I totally agree, the biological basis of this is Pre-frontal Cortex development.
"The [prefrontal cortex] isn't fully developed and won't be until the person is 25 years old or so." https://www.urmc.rochester.edu/encyclopedia/content.aspx?Con...
"This brain region has been implicated in planning complex cognitive behavior, personality expression, decision making, and moderating social behaviour. The basic activity of this brain region is considered to be orchestration of thoughts and actions in accordance with internal goals." https://en.wikipedia.org/wiki/Prefrontal_cortex
I can't understand any other context for drafting 18 year olds other than taking advantage of their youth and incomplete development, but avoiding Presentism and the comfort of Mutually Assured Destruction / Pax Americana, I can understand why when the cards are on the table and your entire society is at risk, why you must call all hands, young and old, into Total War a la WW1 or WW2.
As far as donations go, that's got to be a morally gray area as well for all the reasons you mention.