Armed civility?

The Giffords' shooting has led to a renewed interest in civility as a political virtue that has the potential of controlling vitriol in politics. Vitriolic political speech corrodes democratic politics and civility just like toleration is indeed an important political virtue that could be quite instrumental in controlling vitriol in politics. But bringing guns and rifles to a political gatherings also corrodes democratic politics because like vitriolic political speech it introduces a threat of violence into the democratic political arena. So instead of trusting the possibility of armed political civility, if political civility is to be embraced,  its meaning should be extended to include prohibitions on physical displays that introduce a threat of violence into democratic political spaces.