There is a certain logic to extreme acts, when someone has no other ways left to make themselves heard.

When they get marginalized and oppressed at every turn, and nobody in the world seems to care beyond lip service. When an oppressive regime takes away their rights, their food and water, their schools and jobs, their possessions, their homes, even their means of crying out for help by normal means, people will reach a point where they have nothing left to lose.

And their helplessness and hatred are all that is left, they will not care about lives. Their own, any bystander, all that is left is to hurt the people that hurt them, in an effort to change the situation for their other people.