In a lengthier statement released after the interview, Clinton cast blame on Republicans for blocking Democratic proposals to strengthen the economy, leaving the U.S. in a weakened competitive position. As a result, she said, “we’re going into this with one arm tied behind our backs.”

I still believe in the goal of a strong and fair trade agreement in the Pacific as part of a broader strategy both at home and abroad, just as I did when I was Secretary of State. I appreciate the hard work that President Obama and his team put into this process and recognize the strides they made. But the bar here is very high and, based on what I have seen, I don't believe this agreement has met it.

Trade has been a vexing issue for Clinton in both of her presidential runs. She struggled to defend NAFTA—signed by her husband—in 2008, and she avoided taking a position on TPP for months earlier this year. Her opposition to the final deal also opens her up to charges of flip-flopping, since Republicans have dozens of video clips of Clinton praising earlier drafts of TPP when she was secretary of state—including one in which she said it was “the gold standard” of trade pacts.

In the hour after she announced her position, both the Republican National Committee and Martin O’Malley leveled that exact charge. "Wow! That's a reversal!” the former Maryland governor said in a statement blasted out by his campaign. “I was against the Trans Pacific Partnership months and months ago.”

We were told in NAFTA all sorts of great promises and what we got in return were shuttered factories and empty pockets. I believe we need to stop stumbling backwards into bad deals. Secretary Clinton can justify her own reversal of opinion on this, but I didn't have one opinion eight months ago and switch that opinion on the eve of debates.

Democrats in Congress remain broadly opposed to TPP, but because some leading Republicans have also raised concerns about last-minute compromises by U.S. negotiators, the administration likely will need every Democratic vote it can muster when the House and Senate vote next spring, and Clinton’s opposition won’t help that effort. It also continues a pattern of positions Clinton has taken in recent months on questions like the Keystone pipeline, the Iran nuclear deal, immigration, and guns. She supported Obama on Iran and has gone farther than him on guns and immigration, but in each case, she has sided strongly with the Democratic base.

It’s a much different strategy than the one she pursued, unsuccessfully, in 2008, when she always seemed to have one eye on the general election. This time around, Clinton is determined not to let Sanders get between her and a Democratic base that views her skeptically, even if it means undermining a key legacy item for Obama. The Republicans will just have to wait.

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