AARP, the powerful lobbying group for older Americans, is dropping its longstanding opposition to cutting Social Security benefits, a move that could rock Washington's debate over how to revamp the nation's entitlement programs.

The Wall Street Journal reported in a lengthy piece on Friday that the decision, which AARP hasn't discussed publicly, came after a wrenching debate inside the organization. As the paper noted, in 2005, the last time Social Security was debated, AARP led the effort to kill President George W. Bush's plan for partial privatization. AARP now has concluded that change is inevitable, and it wants to be at the table to try to minimize the pain.

"The ship was sailing. I wanted to be at the wheel when that happens," John Rother (right), AARP's long-time policy chief, told The Journal.

The shift has been vetted by AARP's board and is now the group's stance, and could have a dramatic effect on the debate surrounding the future of the federal safety net.

"If they come around and say they're ready to do something, it will be like the Arctic icecap cracking," former Sen. Alan Simpson, co-chairman of a White House commission on the deficit, told the paper.

At the same time, AARP runs the risk of alienating both its liberal allies, who have vowed to fight any benefit cuts, and its 37 million members, many of whom are deeply opposed to such a move.

Indeed, soon after the announcement, a handful of groups dedicated to preserving Social Security and other benefits for senior citizens sharply criticized AARP’s shift at a time when lawmakers are on the hunt for ways to save money as they negotiate over raising the debt ceiling and over reducing the nation’s debt.

“What AARP has done, in our opinion, in offering up Social Security benefit cuts in order to gain access to closed-door discussions, where let’s-make-a-deal politics has become the norm, is not the way to discuss strengthening a program that touches the lives of virtually every American family,” Max Richtman, acting chief executive of the National Committee to Preserve Social Security and Medicare, said in a conference call with reporters on Friday.