As I've mentioned before, I don't think that even the far-left should demonise the police - the primary reason I mentioned before is that in any new political order, it is likely that some form of policing will be necessary. While in theory some of this might be carried by an active civic community (regular town halls, ability to denounce people for bad things, some consequence structure if shaming is not enough), we neither know if that is capable of doing most of what police do now nor can it be a complete mechanism for dealing with malfeasors. In theory, better education, a more harmonious society, and more equitability in resource distribution might reduce the likelihood of some crimes, but there will always be the criminally mentally ill as well as people who fall through the cracks. That argument is, in sum, we will need police.
Another reason not to alienate the police is that it solidifies any leaning of police away from far-left causes. I don't explore this here, nor do I explore parallels of this at a personal level.
The most hazardous reason not to alienate the police is that dehumanising them, if done broadly enough, is capable of producing the monsters that anti-police activists claim police are anyhow. People are social creatures with social needs, and, like with teachers, police enter their field with both a great responsibility and a need for recognition for their work. While in some fields, performance is relatively habitual and static (bus driver as public servant - still a good idea to thank them, by the way), with these fields, feeling valued by the public is important to keep them from jadedness. The difference between someone who believes they're serving the public good and someone who's just paying the bills in these two fields is immense, and depriving people in any field from the feeling they're doing good transforms them from engaged workers to being fully wage-slaves (wage-slaves who in this case risk their lives).
Police are mechanisms of the existing system, although they do not necessarily endorse all aspects of it. While the existing system is, we contend, fundamentally unjust and in need of replacement, there is much in common with what is and what would be - the status of police as enforcers means that our opposition to them is occasional and situational, but it should not be principled. They may not be fundamentally just, in the sense that they likely would enforce any law that's on the books and traditionally enforced, but they are not fundamentally unjust - they are servants of generic civilisation. We may oppose (even forcefully or violently) their actions when we perform direct action, or should the opportunity arise and we gain the capability to topple and replace the system, or when we break other unjust laws and they would enforce current societal/systemic rules against us, but they are not inherently our enemy. Treating them as such is harmful to our cause, and harmful to any notion of society.
In the general sense, we should seek to recognise the value of anyone's work which has a clear tie to the public good, and to reject and condemn people whose professions do not. Building a strong value-consensus on this opens new paths for fundamental changes in society that might make revolution unnecessary, and should revolution occur, make it more likely to be successful. A capitalist system full of people with socialist virtues is far more likely to come to good things than a socialist system full of people with capitalist virtues.
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