I'm an Arab and a refugee. I've seen middle eastern terrorism upfront as well as brutal opression and torture. Up close and personal. I know what trauma is, and I've never felt the slightest inclination to harm anyone, much less kidnap or kill them.
You are possessed of the typical western attitude to these things, which while well-meaning is also deeply misguided.
This behavior isn't a reaction to trauma. You will not find Ukraine citizens reacting to their trauma in such ways.
In my culture many things are normalised: Jew hatred, violence and opression. Our world doesn't work like yours. It has nothing to do with evil or not evil. All people are capable of atrocity.
It comes down to culture: being told its okay to do this. Being told it's good to do this. And while you might say not all Palestinians are terrorists, I can assure you that the ones who are, are lauded and treated like heroes and celebrities.
Really think about that, because it might give you an understanding of the deep fractures in a society that build up to that, and opression simply doesn't factor in.
The evils conmitted by man through history largely had nothing to do with opression. Black people weren't opressing white people in 1700 - slave traders weren't driven to it by trauma. Something was actually deeply malignant in their ideology and they needed to be educated out of it.
Infantalising this is unhelpful. Palestinian people are no different to any other people, with the exception that they are trapped as pawns in an ideological war and their lives simply do not matter to the very people charged with their governance.
There is objectively no reason they couldn't have spent the last 20, 30, 40 years living really nice lives, aside from the fact that they were trapped in a largely manufactured battle.
We have a great deal of work to do. And anybody who thinks Palestinians are opresssed and traumatised (as I do) cannot solve that problem by simply blaming Israel and pretending the behaviour and existence of groups like Hamas is an Israeli issue. I assure you, it's not.