None of the leading Democratic presidential contenders said they would immediately drop President Trump's tariffs on China if elected president, despite criticizing his moves against Beijing as reckless.

Driving the news: Axios asked each campaign whether they would get rid of the tariffs on day 1, and none gave a clear answer. The campaigns said they would either leave the existing tariffs in place or conduct a review of the tariff policy upon entering office.

Why it matters: Trade with China is one of the few foreign policy issues that must-win Rust Belt voters care about deeply. This is largely because people in Michigan, Wisconsin and Pennsylvania have seen factories close as manufacturing moves overseas — and, subsequently, they have seen their towns gutted.

Between the lines: Despite the steep political polarization in Washington, China's emergence as an competitor has largely unified U.S. politicians. Regardless of the merits of Trump's approach, he has pushed China into the spotlight, experts say.

"Any Dem that doesn’t express a desire to be tough on China digs themselves into a hole before the race even gets going," Scott Mulhauser, former chief of staff at the U.S. Embassy in Beijing and deputy chief of staff to former Vice President Joe Biden during the 2012 election, told Axios.

Tariffs are "a problematic solution to being tough on China," Mulhauser added, noting how they reverberate back onto Americans, but "there are ways to use them as leverage to extract concessions from the Chinese — not only in the trade space but beyond."

Historically, Democrats have dominated Republicans on the China trade issue. Working with their labor allies, they've fought free trade deals with China and backed protectionist policies to shield American manufacturing.

But in 2016, Trump seized that issue and now all but owns it. He's made the GOP the party of China hawks.

“Trump has turned this into a Trump issue; he's put his own mark on it,” said Ned Price, who served as National Security Council spokesperson to former President Obama. "But in doing so he has opened the door to Democrats making a campaign issue out of this."

The big picture: Axios asked the top 2020 Democratic candidates if they plan to take the China trade issue back from Trump, and if so, how.

Sen. Bernie Sanders offered the most concrete response, saying he would go after China hard on climate change, as they are the No. 1 emitter of greenhouse gases. He also said he'd establish "a coalition of allies and partners" to respond to Beijing’s "troubling behavior" in key areas, including disputes over trade and intellectual property.

he would go after China hard on climate change, as they are the No. 1 emitter of greenhouse gases. He also said he'd establish "a coalition of allies and partners" to respond to Beijing’s "troubling behavior" in key areas, including disputes over trade and intellectual property. Former Vice President Joe Biden's foreign policy and climate plans also lay out detailed ways that Biden would target China's climate abuses and make Americans jobs more competitive.

foreign policy and climate plans also lay out detailed ways that Biden would target China's climate abuses and make Americans jobs more competitive. South Bend Indiana Mayor Pete Buttigieg outlined specific areas in which he would work to make the U.S. more competitive with on a domestic level to compete with China, including major infrastructure investments and revised trade and export policies.

outlined specific areas in which he would work to make the U.S. more competitive with on a domestic level to compete with China, including major infrastructure investments and revised trade and export policies. The others, like Sens. Elizabeth Warren, Kirsten Gillibrand and Amy Klobuchar, offered broad statements on how the U.S. could be more aggressive toward China's trade abuses and develop a better relationship with America's allies to further those efforts. But they offered no substantive strategy or new areas to address.

on how the U.S. could be more aggressive toward China's trade abuses and develop a better relationship with America's allies to further those efforts. But they offered no substantive strategy or new areas to address. Sens. Kamala Harris and Cory Booker, Rep. Tim Ryan and former HUD Secretary Julián Castro did not respond to multiple requests for comment. Former Rep. Beto O'Rourke declined to comment.

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