You seem…confused…as to the meaning of the word unprovoked. Medea’s children didn’t do anything to her. She murdered them to hurt Jason–to make him suffer longer than if she had killed him instead, which was surely within her power. The children–her own goddamn sons–weren’t people in her eyes, merely an instrument she used to punish her arrant husband.
I mean, really. Medea murders Jason’s new wife and her her own sons to make him suffer? Hell’s Bells, she didn’t have to murder anyone. She had a freaking chariot pulled by dragons; she could have loaded the kids into that and flown off with them. No one would have gotten in her way; that is what dragon-drawn chariot means.
I read that in some of the early versions, she didn’t kill her kids. It just so happened that the one where she did was made into a popular play and became the one everyone knows.
I think you are reading twentieth century Western mores into Medea where they don’t belong. Children were not people in the eyes of most of society in the time Medea was written and for many centuries afterwards. They were property of the parents. At the time Medea was written, parents could and did sell their kids into slavery (which arguably could be worse than a quick death). And as for the kids’ themselves, they certainly didn’t try to stop their father from leaving their mother, so in my opinion they got what they deserved so did Jason.