Editor’s Note: Each week we cross-post an excerpt from Katrina vanden Heuvel’s column at the WashingtonPost.com. Read the full text of Katrina’s column here.

What a difference a year makes. In 2012, Politico was reporting that Democrats had gone “AWOL in class war.” Occupy had come and gone by the spring. Mitt Romney’s Republican primary rivals were harsher on his “vulture capitalism” than President Obama was. Labor was under siege across the country. Liberals were focused on social issues like gay rights and abortion. The Tea Party had captured the (faux) populist mantle and was still riding high.

No longer. The Tea Party discredited itself with its government shutdown and threat of defaulting on American obligations. And the populist temper in the Democratic Party has been unleashed, once the president was safely reelected.

Now the simmering tensions between what former Senator Paul Wellstone called “the Democratic wing of the Democratic Party” and the Wall Street wing of that party have begun to boil. Populist Bill de Blasio is elected mayor of New York calling for raising taxes on the wealthy to pay for pre-K for every child. Bill Daley, early favorite in the Illinois race for governor, doesn’t make it out of the Democratic primary, as he is skewered as an ex-lobbyist for JPMorgan Chase. The New Republic puts rows of Sen. Elizabeth Warren’s face on its cover with the headline “Hillary’s nightmare.”

The differences between the two wings aren’t cosmetic or personal. They concern the basic direction of the party and the country. The battle is being driven by the harsh realities of this economy. Coming out of the Great Recession, the wealthiest few are capturing nearly all the rewards of growth, while most American families are struggling to stay afloat. The new majority forged by Obama—the “rising American electorate” of millennials, people of color, and single women—is struggling the most.

Editor’s Note: Each week we cross-post an excerpt from Katrina vanden Heuvel’s column at the WashingtonPost.com. Read the full text of Katrina’s column here.