Both problems can be understood as symptomatic of systemic issues, insofar as the underlying pertinence is addressed, the concordant problems will organically whither or taper off.
While it's difficulty to fully assess causes, we can at least be certain of some negatives (i.e. things that don't help, and probably exacerbate issues).
In the case of fascism, an increasingly atomised and economically precarious/directionless youth will be supervened upon by identity politics in the wake of their emptiness. If the promise of said identity politics relates to some notion of inborn/innate superiority for your particular demographic, then it evokes a sense of existential reclamation.
Pedophilia? The media and porn (specifically as far as the fixation on infantilization, i.e. excessive emphasize on the preservation and aesthetic of youthfulness, overly-codified dynamics of submissiveness to the point of sexualized 'cute' docility, don't help. There's even research showing an increase in the likelihood of someone indulging in Cheese Pizza the more depraved and lasting their exposure to porn becomes.