"The same could be said of the actions of almost any religious extremist."

It's hard to know exactly what someone who commits these acts is actually thinking. They may believe someone who has told them that these acts are true acts of faith. They may be holding a grudge. We may never know. There are two things that help me.

1) Their actions (and mine) will eventually be vetted by someone with a clear view of everything, including upbringing, history, intent, etc. And it won't be me.

2) There is a way to know the truth about anything. All you have to do is go to the source.