Especially since police was allowed to get surplus military weapons and vehicles.... so you have a good chance of being heavily outgunned - and you can't anyway fire more than two handguns at a time (and despite movies, you would probably just waste ammunition).
Anyway, I don't know where Americans got this hamster idea that piling up guns in their den will make them safer against the evil government. Do they believe they will still have to face the same troops of a quarter of millennium ago??