The requirements for a sin to lead someone to hell is:
It is of grave or serious matter
It is done with full knowledge of its severity
It is done with full consent
These three rules apply to all mortal sins. If a single one is missing, than it is either not a sin at all or only a venial sin.
In under-developed nations and in tyrannical dictatorships, child soldiers are often employed to fill the ranks of an army. Despite being young in age, they have been known commit brutal atrocities up to and exceeding rape and genocide.
With culpability, it is probably reduced because if the children don’t cooperate, then they would probably die. So it could in a way be seen as not full consent because it’s from outside forces that pressure them into becoming child soldiers. Also, they are taught this from a young age, a time they are most open to being shaped in terms of world views. Some are probably indoctrinated as such before the age of reason.
An Orthodox friend told me that if there are two people, and one of them is living in a very sinful environment, then that person is probably less culpable for the same sin than the person living in a normal healthy environment. Not saying the responsibility of having committed the sin is no longer there, but the culpability is reduced. If these child soldiers were instead raised in a stable family and home, then they probably wouldn’t be committing these grave things. Just something to consider.
However… the simple answer is… we don’t know.
Only God knows the hearts of men and children.
It would seem improbable to me that a child soldier would be in mortal sin. Often times, coercion, drugs, sex and a variety of tactics are used to manipulate the children into deadening their emotions and following orders.
As the above poster noted, the culpability is the key factor here, as obviously the crimes they commit are still objectively grave matter.
So, in short, my answer would be “no”. I can’t see how they would be. At least not in general.
To the first question: are child soldiers capable of mortal sin? Absolutely yes. Most of them are already above the age of reason, which makes them capable of #2 and #3, so they are definitely capable or mortal sin, as is the 12-year old on the playground across the street.
To the second question: are they going to hell? The same answer as for any other human being. We do not know because no one has the ability to judge the state of any person’s soul. This is a question that can have only one standard answer, and therefore is useless to ask.
It is actually not that simple. While 12 years is normally the age of reason, a twelve year old might not be mature enough to meed requirements #2 and #3 if he came from a region where the age of reason was pushed back by environmental factors.
If a child soldier knows he or she will be murdered for not cooperating, than #3 is missing. If a child soldier consents, but his mind is underdeveloped due to childhood malnourishment (a common problem in developing nations, which is where child soldiers come from), than #2 is missing because he thinks it is just a fun game.
The definition of a mortal sin is a sin that is bad enough to land the sinner in hell if he or she is unrepentant.
And I don’t appreciate being told my question shouldn’t even be asked.
My guess is, no, for them they are so traumatized and brainwashed that they do not fulfill #2 and #3.
This is sad, but there is a reason that most countries will not accept child-soldier refugees because there is almost no hope for rehabilitation. It seems outrageous and cruel not to accept these children, but because of their mental state, they are too much of a danger and risk, and rehabilitation is next to impossible. The damage has been done - even if they are still children.
I have to assume that if the specialists, psychologists, sociologists who deal with refugees have determined that rehabilitation is impossible, then these children are a sort of a “feral child,” if you will, and not responsible for their actions. Woe to him who tortured these children to become this way.
That’s why I said they are capable, or if you want to be safer, may be capable. Other factors always come onto play with regards to #2 and #3.
And that’s why that leads to the second answer which you don’t appreciate but which I’ll say anyway. No one knows the state of anyone’s soul, barring special revelation from God, so no one knows who’s going to hell, and the question shouldn’t even be asked because the answer is the same for every human being on the planet: we don’t know.
That is basically writing off all philosophy. Plato, Diogenes, and Socrates didn’t know all the answers, but that never stopped them from asking questions.
Just because you don’t know the answer to a question does not mean it should not be asked; the question will still make us think about how many potential answers there are and may also raise other questions. Since every question makes us think, than every question is worth asking.