One of the duties of the artist – not the only duty, but a central one – is to impel people to imagine the complexity of thought and feeling inside another person. Art complicates moral action, because we have to accept that other people matter, that their hardship and suffering, even their rage and sorrow, are, to some extent, our responsibility.
Propaganda has the opposite aim: it is intended to simplify moral action. People get to disregard the humanity of others. This makes them easier to ignore, deport, imprison, torture, enslave, and kill.