Progressives believe, correctly, that government can and should provide such public goods and services as education, parks, or aid for the poor and disabled. It’s axiomatic that the public is entitled to the highest quality at the best possible price. Yet unions, by their nature, increase the price of public services, without necessarily increasing quality. Just ask New York Mayor Michael Bloomberg about the “rubber room” where, until a couple of years ago, hundreds of union teachers languished, on full pay, while awaiting disciplinary hearings.

Which brings us to equality. To be sure, public-sector pay and perks hardly put union workers in the 1 percent. But their clout enables them to enjoy retirement and health-care benefits that are often better than those available to the middle-class citizens whose tax dollars support them. What’s fair about that? Even after Walker’s bill, Wisconsin public employees pay just 5.8 percent of their salary toward their pensions and a modest 12.6 percent of their health-care premiums…

Maybe there are enough voters in Wisconsin who support actual progressive governance — as opposed to “progressive” interest groups — to retain Walker.