The life experience of most middle class kids growing up in modern industrialized democracies is that all their material needs will be cared for, and that peace is normal. They have easy lives and assume that this is the way things are supposed to be.
Many, when they get to college, are exposed for the first time with full force to the quantity of pain and suffering in history.
What political stance is possible, other than what I call Sybaritic Leftism, if they start with the assumption that pain is aberrant and unnecessary?
How EASY it is for ideologues to pull these kids in, simply by promising them an end to human suffering. Among other things, ease makes people stupid. It takes a long, long time to get out of it.