theory

I think it's really important to extend a charitable attitude towards comrades and that we should all remember that if our communities have a rigorous culture of critique then it means that we're going to be on the receiving end of it at some point, eventually, and that it's going to be better for everyone—ourselves included—if we don't engage in shit-flinging internally.

Externally, go ham. (I usually give libs one or two chances before I get ruthless with them, unless I think they just need a little nudge to radicalise.)

But internally, I think it's of crucial importance that whatever community you're a part of has a really even-handed approach to criticism in order to have strong, healthy community with any chance at longevity. If we look at Mao's short piece Where Do Correct Ideas Come From?:

Where do correct ideas come from?

Do they drop from the skies? No. Are they innate in the mind? No. They come from social practice, and from it alone; they come from three kinds of social practice, the struggle for production, the class struggle and scientific experiment. It is man’s social being that determines his thinking. Once the correct ideas characteristic of the advanced class are grasped by the masses, these ideas turn into a material force which changes society and changes the world. In their social practice, men engage in various kinds of struggle and gain rich experience, both from their successes and from their failures.

And think about that last bit especially—[people] engage in various kinds of struggle and gain rich experience, both from their successes and from their failures—then we need to cultivate a culture where we embrace gaining rich experience from our failures especially and where we encourage it in others. Shitting on people isn't the right way of achieving that goal.

And I'm saying this in full knowledge of the fact that I could just as easily be wrong on this topic btw, not to tell you in some condescending way that you're wrong but we should be nice to you regardless; I've had positions that I've felt more certain about which have turned out to be incorrect in the past.

It's about a ruthless criticism of all that exists, not about being a ruthless jerk to all who exist.