NOW that a Wisconsin judge has temporarily blocked a state law that would strip public employee unions of most collective bargaining rights, it’s worth stepping back to place these events in larger historical context.

Republicans in Wisconsin are seeking to reverse civic traditions that for more than a century have been among the most celebrated achievements not just of their state, but of their own party as well.

Wisconsin was at the forefront of the progressive reform movement in the early 20th century, when the policies of Gov. Robert M. La Follette prompted a fellow Republican, Theodore Roosevelt, to call the state a “laboratory of democracy.” The state pioneered many social reforms: It was the first to introduce workers’ compensation, in 1911; unemployment insurance, in 1932; and public employee bargaining, in 1959.

University of Wisconsin professors helped design Social Security and were responsible for founding the union that eventually became the American Federation of State, County and Municipal Employees. Wisconsin reformers were equally active in promoting workplace safety, and often led the nation in natural resource conservation and environmental protection.

But while Americans are aware of this progressive tradition, they probably don’t know that many of the innovations on behalf of working people were at least as much the work of Republicans as of Democrats.

Although Wisconsin has a Democratic reputation these days — it backed the party’s presidential candidates in 2000, 2004 and 2008 — the state was dominated by Republicans for a full century after the Civil War. The Democratic Party was so ineffective that Wisconsin politics were largely conducted as debates between the progressive and conservative wings of the Republican Party.

When the Wisconsin Democratic Party finally revived itself in the 1950s, it did so in a context where members of both parties were unusually open to bipartisan policy approaches. Many of the new Democrats had in fact been progressive Republicans just a few years earlier, having left the party in revulsion against the reactionary politics of their own senator, Joseph R. McCarthy, and in sympathy with postwar liberalizing forces like the growing civil rights movement.

The demonizing of government at all levels that has become such a reflexive impulse for conservatives in the early 21st century would have mystified most elected officials in Wisconsin just a few decades ago.

When Gov. Gaylord A. Nelson, a Democrat, sought to extend collective bargaining rights to municipal workers in 1959, he did so in partnership with a Legislature in which one house was controlled by the Republicans. Both sides believed the normalization of labor-management relations would increase efficiency and avoid crippling strikes like those of the Milwaukee garbage collectors during the 1950s. Later, in 1967, when collective bargaining was extended to state workers for the same reasons, the reform was promoted by a Republican governor, Warren P. Knowles, with a Republican Legislature.

The policies that the current governor, Scott Walker, has sought to overturn, in other words, are legacies of his own party.

But Mr. Walker’s assault on collective bargaining rights breaks with Wisconsin history in two much deeper ways as well. Among the state’s proudest traditions is a passion for transparent government that often strikes outsiders as extreme. Its open meetings law, open records law and public comment procedures are among the strongest in the nation. Indeed, the basis for the restraining order blocking the collective bargaining law is that Republicans may have violated open meetings rules in passing it. The legislation they have enacted turns out to be radical not just in its content, but in its blunt ends-justify-the-means disregard for openness and transparency.

This in turn points to what is perhaps Mr. Walker’s greatest break from the political traditions of his state. Wisconsinites have long believed that common problems deserve common solutions, and that when something needs fixing, we should roll up our sleeves and work together — no matter what our politics — to achieve the common good.

Mr. Walker’s conduct has provoked a level of divisiveness and bitter partisan hostility the likes of which have not been seen in this state since at least the Vietnam War. Many citizens are furious at their governor and his party, not only because of profound policy differences, but because these particular Republicans have exercised power in abusively nontransparent ways that represent such a radical break from the state’s tradition of open government.

Perhaps that is why — as a centrist and a lifelong independent — I have found myself returning over the past few weeks to the question posed by the lawyer Joseph N. Welch during the hearings that finally helped bring down another Wisconsin Republican, Joe McCarthy, in 1954: “Have you no sense of decency, sir, at long last? Have you left no sense of decency?”

Scott Walker is not Joe McCarthy. Their political convictions and the two moments in history are quite different. But there is something about the style of the two men — their aggressiveness, their self-certainty, their seeming indifference to contrary views — that may help explain the extreme partisan reactions they triggered. McCarthy helped create the modern Democratic Party in Wisconsin by infuriating progressive Republicans, imagining that he could build a national platform by cultivating an image as a sternly uncompromising leader willing to attack anyone who stood in his way. Mr. Walker appears to be provoking some of the same ire from adversaries and from advocates of good government by acting with a similar contempt for those who disagree with him.

The turmoil in Wisconsin is not only about bargaining rights or the pension payments of public employees. It is about transparency and openness. It is about neighborliness, decency and mutual respect. Joe McCarthy forgot these lessons of good government, and so, I fear, has Mr. Walker. Wisconsin’s citizens have not.

William Cronon is a professor of history, geography and

environmental studies at the University of Wisconsin–Madison.