[afiori]

Comunist are also quite bad at that, I have met moderate reasonable people under the comunism banner that were sorta ok with other people calling themselves stalinists.

For example for all the criticism that you can point against religion most religious communities openly and clearly oppose and denounce terrorism.

In my view comunism was never able to separate itselft from a revolutionary mindset, and so agitators and extremists were always (since Marx, at least) considered a planned and likely step.