The issue in Wisconsin and across America is simple and straightforward - a corporate-financed offensive to crush unions, returning workers to 19th century harshness with no rights whatever. [MORE] 

So far, however, the White House has stayed away from any trips to Madison, the state capital, or other states in the throes of union battles. The Obama administration is treading carefully on the contentious political issue that has led to a national debate over the power that public sector unions wield in negotiating wages and benefits.

A few labor leaders have complained openly that President Barack Obama is ignoring a campaign pledge he made to stand with unions; most others say his public comments have been powerful enough.

The stakes are high as Obama looks toward a grueling re-election campaign. Republicans have begun airing television ads linking Obama to "union bosses" standing in the way of budget cuts in Wisconsin, Ohio and other states.

As a candidate, Obama seemed to promise more to organized labor, among the Democratic Party's most loyal constituencies.

"If American workers are being denied their right to organize and collectively bargain when I'm in the White House, I'll put on a comfortable pair of shoes myself," Obama said at a speech in 2007. "I'll walk on that picket line with you as president of the United States of America because workers deserve to know that somebody is standing in their corner."