Ariel's statement is primarily one of recognition - a sudden awareness of the existence of men who are essentially evil - but the language he employs is supernatural in scope. In this respect, it mirrors what some people must be experiencing today - a cold, perhaps even reluctant realization of evil in their midst. Like Ariel, I imagine some would even use demonic imagery to describe this evil, but I suspect such language would remain firmly grounded in the metaphorical in the minds of most. In other words, evil men are merely like devils; hell, the imaginary place from which they spawn.
Though metaphoric comprehension denotes a step in the right direction, it offers only a partial understanding of the reality we are currently experiencing. It is hard to know if all the devils are here in this time and place, but one thing is certain - many are. And their numbers are increasing by the day. The pressure they are building and the chaos they are fomenting is undeniable.
If hell is not empty yet, then we must be getting close - awfully close.