In my humble, outsider (i.e.: non-US) opinion, when weapons get involved (on any side), things escalate. In other words, would something like the Kent University massacre have gone differently if protesters were armed (not considering the ideological weirdness of such a scenario)?
I see what's good in the argument that people should be able to respond to tyranny with force, but I'm wondering how often this could actually happen on such a big scale that it would matter instead of being crushed by the State in a matter of hours or days, at best.
And I furthermore wonder whether weapons being legal would matter much in such a situation.