Dumb Assery
The trappings, accoutrements, and doings of a dumb ass.
Come on guys, let's go home. This sort of dumb assery is going to get us all arrested. Bill, put down that hammer!
Dumb-Assery
The practice of acting foolish or saying something foolish when the circumstance calls for an intelligent response.
The dumb-assery of the press led to an immediate breakdown in communications, causing the riot to escalate into a battle between the police and the citizens.