I’m not american and neither do I know much about these parties at all, but my guess would have been, that while they may not be perfect, they’re still the best options for communist parties? I may be mistaken, since I know so little. Like, would the PSL be a better alternative? If they are, maybe they’re not active in his part of the US? Maybe CPUSA is the most accessible?

These are all speculations tho. I’m looking forward to other more educated insights xD.