I am familiar with the concept of the cooperative economy

You vote in local elections. You look for people with more progressive platforms and you put in the work to get them known. Even if they don’t necessarily want what you want, but their presence would move the overton window in your favor, you help them. I also work with people who want to scrap FPTP voting too. Even if we hard disagree on most issues, something like that is worth working together for. The US is very right wing, very corporatist, and very out of touch with anything not in their social bubble. This is going to take generations of work. Until then, if you are progressively aligned, you only, currently, have one real option at the federal level. Not voting for them doesn’t really hurt them, personally, but it will hurt a lot of people not in charge if the regressive party takes power.

And who knows, might have to pick-up a rifle at some point.