WASHINGTON, DC - JANUARY 16: House Minority Leader Rep. Nancy Pelosi (D-CA) pauses during her weekly news conference on Capitol Hill, January 16, 2014 in Washington, DC. Pelosi called on House Speaker John Boehner to cancel next week's recess until the House passes an extension of unemployment insurance. Getty Images

Global warming has returned to Washington.

An issue that Congress largely ignored since the death of climate and energy legislation five years ago has come back in a most unlikely place: the trade debate.

In a 15-minute speech just before Friday's vote that may—repeat, may—sink the trade package, House Minority Leader Nancy Pelosi repeatedly brought up the impact the "fast track" trade legislation would have on the environment. Saying she was "second to none" in the House on climate change, Pelosi chastised Congress for failing to act on the issue while the fast-track bill was prioritized.

"Time is running out to rein in the consequences of climate change," Pelosi said. "We are slowing down our responses [to climate change] while we should be proactive, and yet here we are fast-tracking [trade] legislation," she added, before affirming that she would vote against the Trade Adjustment Assistance measure, a key part of the trade package.

The TAA vote failed 126-302, putting a halt to the trade bill for now. Republicans are regrouping and say they'll bring back the TAA bill next week.

Progressive Democrats and high-profile environmentalists, including the Sierra Club and the Natural Resources Defense Council, have long voiced opposition to Obama's trade push, contending that it will pave the way for a flood of fossil-fuel exports, undermine key environmental safeguards, and worsen climate change.

But the issue injected itself into the debate with fresh force this week with an amendment from House Ways and Means Committee Chairman Paul Ryan that would block the president from using trade negotiations as an avenue to write future climate deals.

The amendment—which comes on a customs bill that would amend the trade bill—was meant to appease Republican concerns that President Obama would use his negotiating authority to act on climate, but it enraged the Left and appears to be one of the factors that pushed Pelosi over the edge.

She singled out the amendment, playing it against language she wrote 25 years ago on the International Development and Finance Act, which required the World Bank and other multilateral development banks to hold environmental reviews of projects they were funding.

"The connection between the environment and commerce is inseparable," she said.

To be sure, there are plenty of interests pushing to defeat the fast-track bill. In her speech, Pelosi cited protection of American employment and security concerns as well, and labor voices have been among the strongest in opposition to the bill. Many Democratic opponents said they were most concerned about the impact a fast-track bill would have on jobs in their district.

The White House has pushed back against the environmental concerns, with the administration telling supporters that a trade deal can actually strengthen environmental protections. Rep. Steve Israel said that President Obama even talked about climate change when he met with Democrats Friday morning to lobby for the bill. But, he added, "I don't believe that one issue swayed votes."

Pelosi's highlighting of the climate language, however, signaled how strong the environmental opposition has played in the trade debate. Even though the White House has increasingly tied climate change to a variety of issues, it generally doesn't make a splash in Congress' debates over economic policy.

But for opponents of fast-track, anything goes.

Rep. Earl Blumenauer, for instance, a lawmaker widely considered to be a progressive champion, was one of only two Democrats to support fast-track when it was approved by the Ways and Means Committee. That vote earned Blumenauer jeers from environmentalists, including Friends of the Earth, a progressive environmental group that went after the congressman in an ad casting his vote as a betrayal of the environment with devastating consequences for the climate.

Facing attack from his own allies, Blumenauer has called for a slate of environmental protections to be built into the trade push, including measures aimed at holding corporations accountable for violating environmental laws.

"Today's move to delay final decision on the trade package represents a significant victory in the fight to ensure that toxic trade agreements like the [Trans-Pacific Partnership] do not get bulldozed through Congress," said Friends of the Earth president Erich Pica. "The political deals that President Obama cut with Republicans to slash Medicare funding and undermine action on climate change revealed how low Obama is willing to go in selling out ordinary Americans and the environment."

Karthik Ganapathy, a spokesman for 350.org, welcomed Pelosi's speech.

"It's hugely encouraging to see the House Democratic leader buck enormous pressure from a sitting president in her own party, on his top legislative priority, primarily over concerns about what this deal would mean for climate change," Ganapathy said. "She's right. This deal is a disaster for our climate, and her words on the floor today are a clear sign that message is breaking through."


Clare Foran and Alex Brown contributed to this article

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