In retrospect, there were two conspicuous giveaways that Wisconsin Governor Scott Walker was headed for victory in last week’s recall election.

One was that the Democrats’ campaign against him wound up focusing on just about everything but Walker’s law limiting collective bargaining rights for government workers. Sixteen months ago, the Capitol building in Madison was besieged by rioting protesters hell-bent on blocking the changes by any means necessary. Union members and their supporters, incandescent with rage, likened Walker to Adolf Hitler and cheered as Democratic lawmakers fled the state in a bid to force the legislature to a standstill. Once the bill passed, unions and Democrats vowed revenge, and amassed a million signatures on recall petitions.

But the more voters saw of the law’s effects, the more they liked it. Dozens of school districts reported millions in savings, most without resorting to layoffs. Property taxes fell. A $3.6 billion state budget deficit turned into a $154 million projected surplus. Walker’s measures proved a tonic for the economy, and support for restoring the status quo ante faded – even among Wisconsin Democrats. Long before Election Day, Democratic challenger Tom Barrett had all but dropped the issue of public-sector collective bargaining from his campaign to replace Walker.

The second harbinger was the plunge in public-employee union membership. The most important of Walker’s reforms, the change Big Labor had fought most bitterly, was ending the automatic withholding of union dues. That made union membership a matter of choice, not compulsion – and tens of thousands of government workers chose to toss their union cards. More than one-third of the American Federation of Teachers Wisconsin membership quit, reported The Wall Street Journal. At the American Federation of State, County, and Municipal Employees, one of the state’s largest unions, the hemorrhaging was worse: AFSCME’s Wisconsin rolls shrank by more than 34,000 over the past year, a 55 percent nose-dive.

Did government workers tear up their union cards solely because the union had lost its right to bargain collectively on their behalf? That’s doubtful: Even under the new law, unions still negotiate over salaries. More likely, public-sector employees ditched their unions for the same reasons so many employees in the private sector – which is now less than 7 percent unionized – have done so. Many never wanted to join a union in the first place. Others were repelled by the authoritarian, belligerent, and left-wing political culture that entrenched unionism so often embodies.

Even before the votes in Wisconsin were cast, observed Michael Barone last week, Democrats and public-employee unions “had already lost the battle of ideas over the issue that sparked the recall.” Their tantrums and slanders didn’t just fail to intimidate Walker and Wisconsin lawmakers from reining in public-sector collective bargaining. They also gave the public a good hard look at what government unionism is apt to descend to. The past 16 months amounted to an extended seminar on the danger of combining collective bargaining with government jobs. Voters watched – and learned.

There was a time when pro-labor political leaders like Franklin D. Roosevelt and Fiorello LaGuardia regarded it as obvious that collective bargaining was incompatible with public employment. Even the legendary AFL-CIO leader George Meany once took it for granted that there could be no “right” to bargain collectively with the government.

When unions bargain with management in the private sector, both sides are contending for a share of the private profits that labor helps produce – and both sides are constrained by the pressures of market discipline. Managers can’t ignore the company’s bottom line. Unions know that if they demand too much they may cost the company its competitive edge.

But when labor and management bargain in the public sector, they are divvying up public funds, not private profits. Government bureaucrats don’t have to worry about losing business to their competitors; state agencies can’t relocate to another part of the country. There is little incentive to hold down wages and benefits, since the taxpayers who will be picking up the tab have no seat at the table. On the other hand, government managers have a powerful motivation to yield to government unions: Union members vote, and their votes can be deployed to reward politicians who give them what they want – or punish those who don’t.

In 1959, when Wisconsin became the first state to enact a public-sector collective-bargaining law, it wasn’t widely understood what the distorted incentives of government unionism would lead to. Five decades later, the wreckage is all around us. The privileges that come with government work – hefty automatic pay raises, Cadillac pension plans, iron-clad job security, ultra-deluxe health insurance – have in many cases grown outlandish and staggeringly unaffordable. What Keith Geiger, the former head of the National Education Association, once referred to as “our sledgehammer, the collective bargaining process,” has wreaked havoc on state and municipal budgets nationwide.

Now, at long last, the pendulum has reversed. The 50-year mistake of public-sector unions is being corrected. Walker’s victory is a heartening reminder that in a democracy, even the most entrenched bad ideas can sometimes be unentrenched. On, Wisconsin!

(Jeff Jacoby is a columnist for The Boston Globe. His website is www.JeffJacoby.com).