There is no such animus. You are equating self defense to being armed.The author of the Slate article in the topic link called the prosecution "inexplicable" and the behavior of government "idiotic" in this case.
It gets a lot easier to explain if you recognize the animus against self-defense that exists among American hoplophobes.
ALL unarmed people have multiple self defense mechanisms available.
Any animus is directed against lethal tools. And battlefield tools.