There is no other way for him to achieve any of his primary psychological functions now — to maintain a sense of belonging, to evaluate himself as a moral being, to assign meaning to his life — except to destroy the imagined monsters and be a shining hero. Because the stakes are so dramatic, he can perhaps be a great hero — not just an average one.
There is a strong natural instinct to belong to something bigger than oneself. This needs to be channelled into two ways: 1) individuals really need to question what they have chosen to belong to, and 2) society really needs create positive channels for individuals to belong to.
How are we doing on that second part?