Wisconsin governor Scott Walker made history today: His signature made Wisconsin a right-to-work state. This marks symbolic and substantive milestones. Symbolically, half the country now guarantees voluntary union dues. Substantively, Walker has helped demonstrate that right-to-work is a political asset, not a liability.

Until today, unions could force workers to pay dues or get fired in a majority of U.S. states. Walker’s signature makes Wisconsin the 25th state offering workplace freedom. Wisconsin also became the third new right-to-work state in the Great Lakes region in the past three years. Governor Walker has helped make worker freedom fully mainstream.

Moreover, Walker has given legislators across the country the courage to support right-to-work. Gallup polling shows Americans overwhelmingly favor voluntary union dues. But historically few legislators outside the South or Western/Plains states would touch the issue. They feared unions’ political machines.

In 1958, the Ohio Republican party pushed right-to-work. In the fall election unions mobilized and wiped them out electorally. For years politicians remembered this and avoided the issue. Between 1960 and 2010, only four new states passed right-to-work laws.

Governor Walker courageously grabbed hold of this political third rail in 2011. Facing an enormous budget deficit, he curtailed collective bargaining and employee benefits in government. To partially compensate government employees, he made their union dues voluntary and stopped deducting them from their paychecks.

Unions howled and launched recall efforts against Walker and his legislative allies. But the voters rebuffed their efforts. Most of the targeted legislators won reelection, as did Governor Walker. In doing so, Walker demonstrated that unions could not follow through on their political threats. This gave legislators in other states the courage to embrace right-to-work.

Now politicians nationwide are supporting worker freedom. Indiana and Michigan passed right-to-work in 2012. The Missouri state house recently passed right-to-work for the first time in its history. The New Mexico state house has passed right-to-work this year too. Counties across Kentucky have passed right-to-work locally too. Illinois governor Bruce Rauner has also embraced local right-to-work zones. The once glacial expansion of right-to-work has become a flood. Now right-to-work has come to Wisconsin’s private sector.

It is fitting that Scott Walker signed America’s 25th right-to-work law. The climate he helped create has expanded worker freedom nationwide.

 - James Sherk is a senior policy analyst in labor economics at the Heritage Foundation.