(J. Scott Applewhite/AP)

On Friday, the AFL-CIO, the country’s largest labor group and a staunch Democratic ally, issued a biting critique of congressional Democrats’ plan to carve $3 trillion from the country’s debt over the next decade. The union argued that Democrats on the debt “supercommittee” made a strategic blunder by offering cuts to entitlement programs such as Medicare and Medicaid.

“These ‘Super Committee’ Democrats have put all their concessions on the table up front in the vain hope that the Republicans might reciprocate,” AFL-CIO President Richard Trumka said in a statement. “But it doesn’t work that way. In this political climate, concessions beget more concessions – not a workable compromise.”

The Democratic plan, unveiled by Senate Finance Committee Chairman Max Baucus (D-Mont.) on Tuesday at a closed-door meeting, includes more than $1 trillion in new tax revenue – a key Democratic condition in the ongoing debt talks. But it would also cut $500 billion from federal health and entitlement programs, a concession that much of the party’s base would consider anathema.

An aide to a senior Democrat defended the plan, contending that “it wouldn't be a serious proposal if it wasn't being attacked on both the left and right.”

"Finding a real, balanced solution to this problem isn't going to win a popularity contest, and it seems that Democrats on the committee have come to grips with that," said the aide, who spoke on condition of anonymity in order to candidly discuss the panel's deliberations.

Democrats also note that the proposal was offered on behalf of the majority of the Democratic lawmakers on the supercommittee and that the package — which used as its starting point the White House’s position in the summer’s debt negotiations — does not include raising the Medicare retirement age, as Obama’s debt-ceiling plan would have done.

Republicans’ counterproposal would trim the debt by $2.2 trillion over the next decade and would not raise taxes.

In his statement Friday, Trumka renewed his pledge to oppose any Social Security or Medicare benefit cuts. He also seized on the message of the Occupy Wall Street movement that the country’s wealthiest earners need to “pay their fair share.”

“The politicians insisting that the only workable solution to their fabricated crisis involves deep cuts to middle class benefits must not get out into Main Street America enough,” Trumka said. “If they had, they would see that the middle class has already given up too much, while Wall Street and the wealthiest Americans have done all the taking. ... This is the moment we need to raise our voices to let Congress know that we will not stand for dismantling the safety net or letting Wall Street and the wealthiest Americans off the hook.”

Other liberals have also criticized the supercommittee Democrats’ plan.

“My fear is that this is deja vu all over again. ... This is essentially what happened in the Biden talks,” Rep. Peter Welch (D-Vt.) told The Hill newspaper. “The Democrats were putting concrete proposals on the table [including entitlement cuts] and the Republicans never came forward with concrete revenues to match it.”

In a statement Thursday, the Democracy for America political action committee also slammed the proposal.

“This plan protects the status quo for the 1 percent, while the 99 percent are expected to sacrifice vital health care they need to survive,” said Jim Dean, chairman of the Democrat group. “Democracy for America will oppose any Democrat who votes for a plan that cuts Medicare or Medicaid.”

And the liberal Center on Budget and Policy Priorities said in an analysis Friday that the plan “actually stands well to the right of plans by the co-chairs of the bipartisan Bowles-Simpson commission and the Senate’s ‘Gang of Six,’ and even further to the right of the plan by the bipartisan Rivlin-Domenici commission.”

On Thursday, House Speaker John Boehner (R-Ohio) panned the Democratic plan but made no mention of the supercommittee Republicans’ proposal.

The panel has until Nov. 23 to agree to a compromise or else a $1.2 trillion across-the-board spending cut will go into effect beginning in 2013.