It should not surprise that Father Robert Sirico of the Acton Institute should use the fight in Wisconsin  over the right to collective bargaining as an opportunity to defend his spectacularly strange take on Catholic social teaching. But, when he concludes, "There is no a priori reason to back every union demand and no reason for Catholics to feel under any doctrinal obligation to do so," Sirico is being simply disingenuous.
The issue in Wisconsin is not "every demand" but a particular demand, the right to form a union and collectively bargain. And that right has been acknowledged and upheld for 120 years by the highest teaching authority of the Church. Sirico is too busy carrying water for the plutocrats to notice. But, he knows better or should know better.