“Occupy Wall Street” is being absorbed into the existing network of liberal grievance groups, turning what began as an unconventional, generally spontaneous amalgam of demonstrations into simply an apparatus for the professional left’s unending campaign of protests.

The group Rebuild the Dream staged protests on Capitol Hill Tuesday afternoon, flying the figurative ‘Occupy’ flag, and plugging all of its standard talking points about income inequality and corporate political influence.

Scribe reported recently on the increasing presence of Big Labor among Occupy protests. Rebuild the Dream will advance that trend, as the labor groups that support it take a large role in the “Take Back the Capitol” protests.

The Service Employees International Union will be running the protest’s blogging operation. A number of other major labor organizations – including the Change to Win federation, the American Federation of State, County, and Municipal Employees, the Communications Workers of America, and U.S. Labor Against the War – are all Rebuild the Dream partners.

The group is also stocked with virtually every major left-wing grievance group in the country. It is primarily a project of MoveOn.org, and boasts as partners Code Pink, Common Cause, Color of Change, Planned Parenthood, the Working Families Party, the Sierra Club, and Campaign for America’s Future, among others.

In other words, the protest taking place at the Capitol will be an entirely ordinary outgrowth of left wing protest politics. If the Occupy protests began as an unconventional movement that rejected mainstream politics and sought broad ideological appeal through its calls for reining in crony capitalism, it is quickly being co-opted by groups looking to advance a generic – and highly partisan – political agenda by leveraging Occupy’s populist appeal.