Hoover had presented a logical death trap. If anyone accuses you of being communist, or communist-adjacent, no defense is possible. If you are simply promoting mild social reform, well, that is exactly what a communist would do, in order to conceal their true motives. If your numbers are insignificant, that is only further proof of your deviousness, as your comrades are all lurking in the shadows. And if there are a lot of you, or you’re openly, proudly communist, that’s just as bad.