Top-tier Democratic candidates finally got into it over trade at the Democratic debate.

The friction between the top progressive Democratic presidential candidates — Bernie Sanders and Elizabeth Warren versus free-trade-friendly Vice President Joe Biden and Kamala Harris — had been building for some time, and it finally came out in the open on Thursday night.

This is all to say that Democrats showed their differing attitudes toward trade, which is one of the issues where presidents have an enormous amount of power.

On Thursday, the divide was roughly exemplified by Sanders targeting Biden’s record of voting for free-trade agreements over the years in the Senate. Biden, meanwhile, sought a middle ground, dismissing concerns about a trade deficit with China while trying to focus on alleged IP abuses instead. Warren largely sidestepped the Sanders-Biden fray while signaling her intention to implement a much more muscular trade agenda than the free-trade-friendly centrist consensus of the last few decades. Meanwhile, Harris, who has occupied fourth place in the polls, cautioned that she’s not some “protectionist Democrat.” “We’ve got to sell our stuff,” she said, seemingly defending Obama’s approach to free trade.

Trump has, through his tariff-driven trade war, stretched the bounds of what a president can do unilaterally to affect the US economy with trade policy, which means the next president could have a lot of room to navigate.

In a Democratic primary, with unions as such a critical constituency, candidates almost always say they have some reservations about the free-trade agenda. The question is how they would actually govern, and we got a bit of a peek into that during the debate.

Bernie Sanders used trade to go after Joe Biden. Elizabeth Warren didn’t.

Sanders and Biden have had similarly long careers in Congress, but they have taken decidedly different approaches to trade during their tenures.

Sanders boasted that he voted against the North American Free Trade Agreement in the House in the 1990s, pointing out Biden voted in favor of NAFTA in the Senate. He associated Biden with the long-term stagnation of American wages, for which people on the left blame long-standing trade policies that they say led to outsourced jobs.

“There is a reason why, in the last 45 years, the average American today, despite an explosion of technology and worker productivity, is not making a penny more than he or she made 45 years ago. And one of the reasons is that, for decades, we have had disastrous trade policies. I have to say to my good friend Joe Biden,” Sanders said, gesturing to his left, “Joe and I strongly disagree on trade.”

Sanders said he “led the opposition” to NAFTA in Congress and blamed the agreement, which Trump is notably trying to renegotiate right now, for the loss of 4 million American jobs. (Fact-checkers have disputed this figure, though it’s possible Sanders was conflating estimates about NAFTA-driven job losses with job losses to China, a mistake PolitiFact has actually dinged Trump for making.)

NAFTA is one of those issues where Sanders and Trump do share some of the same rhetoric. But after calling out Biden, Sanders also made a pointed jab at the president.

“Trump, obviously, hasn’t a clue,” Sanders said. “Trump thinks that trade policy is a tweet at 3:00 in the morning. What we have got to do is develop a trade policy that represents workers, represents the farmers in the Midwest and elsewhere who are losing billions right now because of Trump’s policy.”

Biden dismissed some of the anti-trade concerns heard from Sanders. “The fact of the matter is, China, the problem isn’t the trade deficit,” he said. He pointed to intellectual property theft and steel dumping as the more immediate problems presented by China that need to be addressed.

In the style of people who generally support free trade, Biden made the case for America’s global leadership. As trade experts have told Vox previously, every Democratic candidate is going to talk tough on China as a gesture to working-class voters and organized labor. The real difference is in how they talk about it.

“We’re either going to make the policy or China’s going to make the rules of the road,” he said. “You need to organize the world to take on China, to stop the corrupt practices that are under way.”

Warren, on the other hand, avoided a direct critique of the Biden record (she was asked about what President Obama got wrong but didn’t mention him or his vice president by name), while still promising a change from the prior consensus, saying, “Our trade policy in America has been broken and it has been broken because it works for giant multinational corporations and not for much of anyone else.”

She argued trade policy could be used as a critical tool for pursuing progressive interests on issues like workers’ rights and climate change.

“Everybody wants access to the American market. That means that we have the capacity to say right here in America, you want to come sell goods to American consumers? Then you got to raise your standards,” she said. “You’ve got to raise your labor standards. You’ve got to raise your environmental standards.”

Democrats are quick to say Trump’s bad on trade. They don’t go far from that.

Critics of a progressive trade agenda — as Sanders and Warren espouse — say the actual progressive trade policy wouldn’t be markedly different from what Trump is doing. Democrats across the ideological spectrum were quick to decry Trump’s trade agenda.

“We’ve got a guy in the White House who has been erratic on trade policy, he conducts trade policy by tweet,” Harris said. Sanders echoed the same line and decried farmers “losing billions right now because of Trump’s policy.”

But outside of painting a moral vision for trade — one that protects workers in the United States and abroad; puts environmentalists and human rights activists at the negotiating table; and puts a check on major corporations looking to cut costs — the candidates stayed away from how a trade policy should actually work.

At the third debate, some of the candidates were asked point-blank: “Would you repeal the tariffs on your first day in office and if so, would you risk losing leverage in our trade relationship with China?”

It’s a politically challenging question: Say yes and candidates risk alienating the manufacturing sector in the United States. Say no and rural America, which has been hit hardest with retaliatory tariffs on American agriculture, will have some questions. Only entrepreneur Andrew Yang and South Bend Mayor Pete Buttigieg were asked directly; neither said he would repeal the tariffs on day one.

“I would not repeal the tariffs on day one, but I would let the Chinese know we need to hammer out a deal,” Yang said.

Buttigieg said, “I would have a strategy that would include them as leverage. It’s not about the tariffs. The president has reduced the entire China challenge of a question of tariffs.”

The overwhelming position from Democrats is the United States has to do better. It has to negotiate better and reach better deals. The candidates staked out their talking points on trade but there wasn’t a very robust back and forth on how they’d use their position differently.

There are a lot of candidates claiming middle ground on trade

Historically, Democrats have always been more skeptical of trade. Republicans have been the ones seeking the free-trade agreements, with a narrower sliver of mainstream Democrats joining them over the objections of their left wing.

NAFTA, which was first negotiated by George H.W. Bush but shuttled through Congress by Clinton, was passed with half of the House Democrats, along with a handful of conservative Republicans, voting against it.

But in the past two decades, that political breakdown has been less true of Democratic presidents like Clinton and Obama, who pursued free-trade agreements, while Trump has steered his party toward a more trade-skeptical approach.

In the 2020 field, Warren and Sanders make up the vocal trade skeptics. There are the trade-friendly Democrats like former Rep. Beto O’Rourke and former Vice President Joe Biden who stake out more of a Clinton/Obama-esque free-trade position. Going into Thursday night’s debate, candidates like Harris and Buttigieg were kind of stuck in between.

Harris noticeably staked out a more free-trade position during the debate.

“I’m not a protectionist Democrat,” she said. “When we look at this issue, my trade policy, under a Harris administration, is always going to be about saying, we need to export American products, and to do that we have to have a meaningful trade policy.”

But still, a lot of the candidates in the field are trying to bridge the same gap Obama tried to between a populist agenda and free trade. They are calling for strong international markets but with higher standards. That didn’t work too well for Obama, whose signature trade policy, the TPP, has been thrown out completely.

And it means that the debate around trade all feels a little abstract. “Negotiate better trade deals!” isn’t that different from what Trump was calling for during the 2016 campaign.

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