If you look at bullying logically, then you can see it’s the root of all evil. Not money, but bullying. That’s all it takes: the imposition of your will, your desires, your wishes, on another human being by force or intimidation.
You can see it in Rwanda just as easily as you can see it in the schoolyard: «I can make you do what I want you to do, because I’m stronger than you. It’s not that I’m smarter or I’m more ethical or I’m more entitled. I’m simply stronger.»