One major theme of "The Monsters Are Due on Maple Street" is that mankind is its own worst enemy. For example, when all of the power is out and absolutely nothing works, Les Goodman's car suddenly starts up. The people of Maple Street see this as an opportunity to use Les Goodman as a scapegoat for being the alien. Another example would be when the group was arguing, a dark figure approached the town, and without thinking, Charlie shot it only to find that it was Pete Van Horn. After this, the group's suspicion turns over to Charlie, destroying their relationship and leading to even more arguing. Lastly, at the end of this story, the focus shifts to two aliens who say, "They pick the most dangerous enemy they can find... and it's themselves." This explains the fact that if there is a chance that someone is to blame, humans will take it. To sum it all up, "mankind is its own worst enemy" is the theme of the book, "The Monsters Are Due on Maple Street."
The Monsters Are Due on Maple Street Theme: Mankind is its own worst enemy