@dlowan,
The starting point for this sub-thread was the claim that unions benefit foreign workers. I am saying that to evaluate this claim, you have to look at the actual consequences to
all foreign workers -- including those who would be immigrating without union policies, but can't come because of them.
Unions exist to benefit their members. One benefit of unions to their members is that they keep wages high -- by, among other things, excluding competition that might undercut them. Although I would indeed prefer completely open immigration, and would indeed prefer minimal legal restrictions on wages, that's not the point I'm arguing at the moment. For the moment, I'll settle for calling things what they are: Australian unions benefit their own (domestic) members, benefit some foreigners, and hurt other. That's their right. But there's no need to pretend they are doing foreign workers, as a group, a favor.