Trump's tariffs were already unpopular with voters before he fired his latest shot in the China trade war

• President Donald Trump's tariff policy was unpopular even before he escalated a trade war with China on Monday.
• Polls have largely shown pluralities of voters nationally and in key midterm states who believe tariffs will do more to hurt than help.
• China retaliated against Trump's latest move, and Trump could hit back at Beijing yet again.

By slapping new tariffs on Chinese goods Monday, President Donald Trump ratcheted up a policy that has so far failed to resonate with voters.

The president escalated a trade war with China by slapping 10 percent duties on $200 billion of Chinese products. The levies will rise to 25 percent at the end of the year. Beijing said Tuesday that it will retaliate by putting tariffs on $60 billion worth of U.S. goods next week.

Trump won the White House in 2016 partly on a pledge to revise free trade deals to protect American workers — a promise that resonates with many Republicans and Democrats alike. But tariffs, Trump's mechanism to push trading partners to strike new deals, have more voters than not worried about economic damage and more expensive goods, according to polling.

An ongoing and widening trade war poses political risks for Republicans as they try to stop Democrats from taking House and Senate majorities in November's midterm elections. Trump seems aware of the dangers, as China has retaliated against crops and other American products made in parts of the country that supported the president.

On Tuesday, Trump said China is "actively trying to impact and change our election by attacking our farmers, ranchers and industrial workers." In tweets, he said those Americans "are great patriots" and threatened "great and fast economic retaliation against China" if it targets those industries. The Trump administration has also promised $12 billion in aid to farmers punished by lower prices caused by tariffs.

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Trump promised Monday to impose tariffs on an additional $267 billion in Chinese goods if Beijing hits back in any way. Another escalation could bring even more political risk for the president's party.

A quarter of registered voters nationally think raising tariffs will do more to protect American jobs and help the U.S. economy, according to an NBC News/Wall Street Journal poll in July. Meanwhile, about half of registered voters said duties will do more to raise the costs of goods or hurt the economy. Sixteen percent responded that levies will not have much of an effect.

At the same time, the proportion of Americans who say free trade has helped the U.S. climbed in 2018 relative to past years, according to NBC/WSJ polls. Those figures come with a caveat: Trump has said his ultimate goal is to secure free and fair trade with major partners.

Voters in a handful of critical midterm states have also largely rejected tariffs, according to recent polls. Solid pluralities of registered voters in Illinois, Indiana, Missouri, Pennsylvania, Tennessee and Texas said tariffs will do more to increase costs of products and harm the economy.

While NBC and Marist have so far not polled other politically important states on the issue, it has become a major point of attack for several Democrats. Sen. Heidi Heitkamp, a Democrat defending her seat this year in red farm state North Dakota, recently unveiled an ad contending her Republican challenger, Rep. Kevin Cramer, has not done enough to fight the effects of tariffs.

Montana's Sen. Jon Tester, another Democrat fighting to keep his seat in a pro-Trump state with a heavy farm presence, has sounded alarms about the effects of tariffs. And Democratic Sen. Claire McCaskill, running in a tight race in Missouri, where tariffs are unpopular, has brought up the issue frequently.

The Washington Post and the Schar School at George Mason University also polled individuals in congressional battleground districts, classified as a "toss-up" or "leaning" toward one party. In competitive House districts, 42 percent of those surveyed said tariffs would be "good" for jobs in the U.S., while 57 percent responded that they would be "bad."

One in 5 respondents said duties would be "good" for the cost of products in the U.S., while more than three-fourths said the levies would be "bad" in regard to costs.

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