US VS. THEM:

Obama wasn't through. He wanted me to know, in pointed terms, that for all the talk about her populist convictions, Warren had a personal brand she was trying to promote, too.

"The truth of the matter is that Elizabeth is, you know, a politician like everybody else," he said. "And you know, she's got a voice that she wants to get out there. And I understand that. And on most issues, she and I deeply agree. On this one, though, her arguments don't stand the test of fact and scrutiny."

This is remarkable stuff for Obama. All presidents are forged, in a sense, by the moments at which they come to public life. Obama entered politics during Bill Clinton's presidency, when urban liberals were growing disgusted with the president's strategy of "triangulation," popularly interpreted as the idea that you can win broad support by picking fights with the ideologues in your own party. Obama has always been reflexively averse to anything that might be construed as him pushing back against his friends to score political points with everyone else.

Throughout his presidency, Obama has mostly avoided public feuds with what his first press secretary, Robert Gibbs, liked to call the "professional left" -- even when it's meant sidestepping important disagreements on policy. Democratic politicians and interest groups, in turn, have been cautious in their criticism, offering only muted resistance when Obama stepped up the war in Afghanistan, or when he nearly negotiated a deal that would have restructured entitlements.

But like a marriage in which the spouses pretend to be happier than they really are, Obama's polite alliance with the populist left appears to be suddenly crumbling under the weight of free trade. The more Warren and Senate colleagues like Bernie Sanders and Sherrod Brown attack the proposed Trans-Pacific Partnership, joined by big unions and environmental groups, the more liberated Obama seems to feel in portraying them as reckless and backward-looking, much as Clinton might have done. 

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