By Vivian Salama and Ken Thomas 

WASHINGTON -- President Trump has worked to sell voters on the idea that he can negotiate better trade pacts. Now, as talks drag, he says only he is tough enough to walk away from a bad deal.

Democrats jockeying to face him in 2020 are making the opposite argument as talks with China hit an impasse -- that the administration's performance on trade demonstrates why Mr. Trump is the wrong person for the job.

Mr. Trump on Friday sought to ease tensions over trade with allies such as Canada, Mexico and the European Union. But he continued to criticize what he sees as unfair trade practices -- by Canada in particular -- and said he would put an end to any such imbalance.

"Aren't we tired of being ripped off?" he said.

Mr. Trump is also casting the standoff with China as a cautionary tale for what would happen if Americans voted anyone else into office, after recently accusing the Chinese of reneging on their commitments during trade negotiations.

"China is DREAMING that Sleepy Joe Biden, or any of the others, gets elected in 2020," Mr. Trump wrote recently on Twitter, referring to the former vice president, who launched his presidential campaign last month. "They LOVE ripping off America!"

Democrats have assailed Mr. Trump for his handling of the trade negotiations, pointing to weakening commodity prices for Midwest farmers and the ramifications of what they see as breakdowns in international alliances.

"He has so alienated the rest of the world. I don't know how you think you're going to be able to fundamentally change China going it alone," Mr. Biden recently told reporters in Concord, N.H. "We poke our friends in the eye and then we say we are going to get in a trade war with China?"

Massachusetts Sen. Elizabeth Warren recently warned against what she calls "tariff negotiation by tweet."

"The Chinese are bad actors on trade," Ms. Warren said in Kermit, W.Va. "That means that our best way to fight back is with strength and with a coherent plan -- not with hands."

The yearlong trade dispute with China escalated earlier this month as talks deadlocked. On May 10, the U.S. imposed duties on $200 billion of Chinese imports. In response, China said it would raise tariffs on roughly $60 billion worth of U.S. imports on June 1.

Many voters appear wary of Mr. Trump's approach toward China. A Fox News poll conducted May 11-14 found that 34% of registered voters believed increased tariffs on imports from China would help the U.S. economy, while 45% believed they would hurt. And, by a four-point margin, the survey found voters believed that Mr. Biden would do a better job than Mr. Trump at protecting U.S. interests with China.

While Mr. Trump has said an agreement with China could be reached soon, he has political incentives for the impasse to linger deep into the 2020 campaign. His path to re-election, in all likelihood, rests on his performance in industrial states he carried in 2016 such as Michigan, Ohio, Wisconsin and Pennsylvania -- potentially fertile ground for a message that the president is fighting China.

In his 2016 campaign and since, Mr. Trump has touted his business savvy. He has criticized previous trade deals with Canada, Mexico and China and promised to cut better deals with some of America's biggest trade partners.

Mr. Biden, the leading Democratic presidential contender, has a lengthy record from his 36-year tenure in the Senate, including votes in favor of the North American Free Trade Agreement in 1993 and normalizing trade relations with China in 2000.

During a campaign stop in Iowa earlier this month, Mr. Biden spoke of his optimism for America's economic positioning across the globe, declaring, "China is going to eat our lunch? Come on, man," he said, later adding that China was "not competition for us."

That drew a response from one of Mr. Biden's chief rivals, Vermont Sen. Bernie Sanders, who tweeted that it was "wrong to pretend that China isn't one of our major economic competitors," pointing to the loss of 3 million manufacturing jobs since 2000.

The president has also branched out with his critiques. At a recent campaign rally in Florida, Mr. Trump joked that he would love to watch Democratic hopeful Pete Buttigeig, the mayor of South Bend, Ind., take on the Chinese.

"We have a young man, Buttigieg. Boot-edge-edge. They say 'edge-edge'," he said, sounding out the mayor's last name. "He'll be great representing us against President Xi of China," Mr. Trump said to laughs from the audience. "That'll be great."

Mr. Buttigieg dismissed the president's "name-calling," telling reporters in California that Mr. Trump's comments made him think "of a Chinese proverb that goes, 'When the wind changes, some people build walls and some people build windmills,'" Mr. Buttigieg said. "You've got to recognize that we need something completely different than what we've got in this White House."

Write to Vivian Salama at vivian.salama@wsj.com and Ken Thomas at ken.thomas@wsj.com

(END) Dow Jones Newswires

May 19, 2019 07:14 ET (11:14 GMT)