When the Communists listed it as a desideratum to discredit the FBI, maybe stunts like this would be how. Peter knows he’s going down sooner or later but he’s taking it for the loyal team.
I did wonder if he could be the thread to begin the unraveling of the whole affair. Thought at the time that’s why the FBI were propping him up. That’s why he’s smug; they have to take care of him because he knows so much, and there’s so much more to know! Sure hope you’re right.