Even if the argument was correct, i don't know how this person expects someone else to treat them as a comrade when they themselves show such a callous lack of empathy toward fellow workers. Especially when they pretend to care about the exploitation of workers, you'd think they would at least acknowledge that undocumented people are also - in fact even more! - exploited and vulnerable. There is always a way to make your point without using the kind of awful, dehumanizing language that they use here. If there was any indication that they at least made an effort to sympathize and put themselves in the shoes of the undocumented workers that they are scapegoating, then maybe a discussion could be had. Someone could patiently explain to them why their argument is wrong and misguided, and why solidarity is the better strategy even just from a pragmatic point of view. But as it stands i don't see how anyone is supposed to engage with this kind of post... When you make it clear that you value some human beings less than others merely because of their legal status or place of birth, then you don't get to call yourself a communist.