I advise you not to take Peter Singer too seriously, even if he takes himself very seriously. He's good at stirring people up, because he exploits contradictions in widely accepted conventions, but he doesn't know how to answer the questions he raises.
In other news, I don't see why struggling against the bourgeoisie in one's own nation might not also amount to national chauvinism. It seems like a misapprehension of one's situation, since the opposite party, the bourgeoisie, is global. I would think the proper course of action for a union would be to organize internationally, and where independent unions are forbidden, to work politically to change the laws or government in those states, rather than to confine one's attention entirely to one's own locality. I realize this is mere liberalism, but I'm speaking to the case at hand within the framework given above.
-- Gordon