President Donald Trump on Thursday announced tariffs on polysilicon and its related products, in his administration’s latest attempt to eliminate China’s choke points in the global supply chain for solar panels and semiconductors.

But Trump’s directive won’t take effect until Dec. 4 — well after November’s midterm elections and a planned September summit between Trump and Chinese leader Xi Jinping — as the administration grapples with voters complaining of high prices and fragile trade negotiations with China.

“This will bring the supply chain here,” Commerce Secretary Howard Lutnick said of the order on Thursday alongside Trump at the White House. “We’ve got the industry here, it’s too small, and it’s going to explode.”

Because polysilicon is used in semiconductors and solar panels, it’s essential for military hardware and everyday electronics like cell phones and laptops, in addition to the world’s fastest-growing energy source.

The order imposes a 15 percent tariff on imported polysilicon and its derivatives, as well as minimum prices for imports of polysilicon, polysilicon ingots and wafers, solar cells and solar modules.

It also includes a clause intended to prevent companies from stockpiling those materials between now and December, authorizing Customs and Border Protection to restrict imports if it suspects an importer is attempting to dodge the higher duties.

Trump’s order is the result of a Commerce Department investigation launched last July into national security risks in the polysilicon supply chain, as part of a broader effort to shift supply chains away from China for multiple industries including wind turbines and robotics.

China has a near-monopoly on the production of polysilicon, according to S&P Global. But recent U.S. efforts to limit key areas of trade with China have already drawn a backlash from Beijing, which earlier this week implemented new controls on drone exports to the U.S.

The White House emphasized the order’s impact on domestic semiconductor production, a key focus as the U.S. looks to build out infrastructure related to artificial intelligence. Trump said the U.S. will “have a big percentage of the chip business by the time I leave office.”

But Thursday’s order may have a big impact on the solar industry, according to Jon Toomey, president of the pro-tariff Coalition for a Prosperous America organization.

“This proclamation delivers the most significant global trade protection action for the American polysilicon and solar industry in the modern era,” Toomey said in a statement. “For the first time, the United States is protecting the entire solar supply chain with a single action — and rewarding the manufacturers that build here — while taking a significant step to bolster the domestic semiconductor supply chain.”

President Donald Trump on Saturday abruptly called off the “biggest attacks since World War II” against Iran in favor of negotiations, the latest in a seemingly endless series of whiplashes in the conflict.

The energy markets, which typically favor stability and predictability, responded with little more than a shrug.

Crude prices dipped slightly and gas prices remained steady. Even as the war stretches past the six-month mark and the midterms creep closer, Trump has been able to keep retail prices lower than experts say they should be through the sheer power of promises – which have yet to come through – of a swift end to the conflict. On Monday, he took that a step further, chastising the major oil companies for “making too much money” off global oil shortages as a result of the war.

“They better cut the retail price, the consumer price,” Trump said. “I’ll say it loud and clear. I’m not happy about it.”

But Trump’s ability to jawbone the markets may be diminishing at a critical time, three months before the midterm elections when control of Congress is hanging in the balance and his approval is sinking to new lows amid voter anger over cost of living concerns. It comes as global crude oil supplies are running low, the war threatens more energy flows, refiners are running out of spare capacity and the administration has few tools to keep gas prices low.

“Labor Day is the point where gas prices are baked into the election,” said Republican pollster Frank Luntz. “That last summer trip determines how voters evaluate their cost of living.”

And the higher gas prices come at a time when Trump repeatedly promises to escalate the war and then says it’s almost over a few hours or days later. That is starting to degrade his ability to cause price drops, a former adviser cautioned.

“His credibility has been a little bit shot,” said a former Trump adviser close to the White House, granted anonymity to avoid reprisal.

“The markets aren’t paying attention to him, they’re paying attention to what’s happening and, with respect to oil prices, it is a huge liability for the Republicans,” the adviser said.

Trump on Monday acknowledged that dynamic but expressed no urgency. He told reporters in the Oval Office that he was in no rush to end the conflict, though he acknowledged the need to fully reopen the Strait of Hormuz, through which about 20 percent of global energy supplies flowed before the war. He hinted at the midterm stakes for his party if the conflict does not end soon.

“I’m under no time constraint,” he said. “I don’t happen to be running, but a lot of very good Republicans are running.”

Trump’s ability to move the markets may be the only tool the administration has left to keep gas prices in check, said Rory Johnston, an oil market researcher and founder of the Commodity Context newsletter.

The Trump administration has drawn down the U.S. Petroleum Reserve to its lowest level since President Ronald Reagan’s first term. Oil majors are warning that the lack of refinery capacity could keep prices high for the foreseeable future.

“The market is so entrenched on this idea that eventually this will resolve by Trump deciding and ceding some ground on some issue, likely kind of even symbolic control of the Strait of Hormuz,” he said. “So the market’s going to be constantly watching for any sign that he’s shifting there.”

While experts continue to marvel at Trump’s ability to get the markets to bend to his whims, there is little consensus on when that power will dissipate.

Trump has “less credibility” in terms of moving markets, but it has not totally dissipated, Patrick de Haan, head of petroleum analysis at pricing service GasBuddy.

“I don’t think credibility completely goes to zero,” he said. “Hard to know though when it really bends.”

Trump’s push to keep energy prices low has also been buoyed by reduced Chinese oil imports, the successful rerouting of about 7 million barrels per day of Saudi Arabian crude through the Red Sea and releases from strategic petroleum reserves.

The administration released nearly 3 million barrels of oil from the Strategic Petroleum Reserve last week, bringing the reserves down to their lowest level since February 1983, according to Department of Energy data. About half of the 218.5 million barrels the Department of Energy said it would make available to the market have now left the salt caverns along the Gulf Coast.

As the summer driving season winds down, consumers expect gas prices to fall as well.

If the national average price of a gallon of gas is still above $4 by Saturday, de Haan noted, it will set a new record for the latest in the calendar year that prices are so high.

Ben Lefebvre contributed to this report.

Washington is again ratcheting up the pressure on the European Union with new tariff threats. Brussels’ response is strikingly different from a year ago: Don’t retaliate, don’t put on a show for Donald Trump, and don’t let him dictate the timetable.

Trump’s recent threat to “immediately initiate” a trade investigation over the European Commission’s $1 billion fine against Google came on top of new tariffs on the EU and dozens of other trading partners, and continuing pressure from Washington over drug pricing.

But rather than sounding alarms and scrambling to respond to this new phase of Trump’s global trade war, the EU has shown public restraint — a reaction that suggests that the 27-member bloc has become less susceptible to Trump’s pressure tactics.

This year, European capitals saw their united rejection of Trump’s Greenland ambitions fail to trigger a wider transatlantic rupture. His most sweeping tariffs were struck down by the Supreme Court, and their successors have drawn legal challenges. Now, with a chance that Trump’s grip on Washington loosens in the November midterm elections, Europeans are happy to play for time.

“It is a strategy of buying time through dialogue,” Bernd Lange, a German member of the European Parliament and chair of its Committee on International Trade, said in an interview. “The Commission’s approach is to move away from anything that could be seen as legally binding and focus instead on dialogue forums, consultation and areas where cooperation is possible.”

Last year, Brussels repeatedly bristled at Trump’s tariff threats, which at times reached as high as 50 percent, before agreeing to a trade truce at the U.S. president’s golf resort in Turnberry, Scotland. After months of delays that tested Washington’s patience, the EU fulfilled its side of the bargain by passing legislation in June to allow U.S. industrial and some agricultural goods to enter the bloc duty-free.

A USTR official, granted anonymity to share the administration’s thinking, credited the EU for implementing “key commitments,” in the Turnberry deal, “such as massive tariff reductions for U.S. exports, and has made concrete commitments on a number of other burdensome regulatory matters.”

“Any technical talks will be about implementing the remaining commitments, and the U.S. side anticipates this will move at pace,” the official added.

The White House did not respond to a request for comment.

The EU law, however, also includes guardrails should Trump threaten the bloc again.

It didn’t take long for him to do so.

While the 10 percent tariff the U.S. government rolled out July 23 does not violate the Turnberry agreement, which caps U.S. duties on most EU goods at 15 percent, Trump’s threats to investigate Europe’s digital restrictions in the wake of the Google fine would likely do so. The Office of the U.S. Trade Representative has yet to launch an official investigation, but the official there confirmed to POLITICO that the agency expected “to initiate the investigation soon”. That could allow the White House to layer on more tariffs on EU imports.

U.S. Trade Representative Jamieson Greer is also conducting a separate trade investigation into Germany’s pharmaceutical pricing and has suggested he could launch similar reviews of other European countries’ drug pricing practices as well.

Those investigations, however, will take months to resolve, if not longer.

“The second phase of the trade war touches a nerve in Europe: sovereignty. Whether it concerns taxation, health care systems or competition policy, these are areas the EU sees as core to its autonomy,” said Jeromin Zettelmeyer, a former International Monetary Fund and German government official who now heads Brussels-based think tank Bruegel.

“At the same time, Trump no longer appears as politically untouchable as he did at the start of his presidency. Weakening poll numbers ahead of the midterms, controversy over the Iran war and legal setbacks in the U.S. Supreme Court have exposed vulnerabilities,” Zettelmeyer said.

In the meantime, EU officials are keeping channels to Washington open. The thinking in Brussels is that every public confrontation plays to Trump’s preferred negotiating style, whereas slower legal and technical processes give the EU more room to manage disputes on its own terms.

Nor is German Chancellor Friedrich Merz in a rush to offer concessions to the Trump administration on drug pricing, according to a European official familiar with the issue who was granted anonymity to discuss the sensitive talks. Berlin expects the U.S. trade investigation to take at least a year, the person noted.

Brussels is in close touch with Berlin on the probe, which it believes could be a blueprint for other possible U.S. trade investigations into France and Italy’s pharmaceutical policies. Ditte Juul Jørgensen, head of the Commission’s trade department, recently met with German officials in Berlin to focus on a way forward on drug pricing.

The Commission has adopted a similar strategy on transatlantic disagreements on digital policy.

While the Trump administration has pressed for broader talks, including on the enforcement of the EU’s competition rules governing Big Tech platforms, Brussels has taken pains to keep the discussions at a technical level.

In early July, a group of officials from the European Commission’s trade and tech departments headed to Washington for what a Commission spokesperson described as “a dialogue on the dialogue.”

A senior Commission official said the meeting was about seeing where the two sides could “partner up,” with Brussels looking at holding a “high-level” meeting with Washington in the fall and a series of technical rounds in between.

“From the EU’s perspective, both sort of genetically as an organization and tactically, they would be happy if as many of the discussions as possible moved to the technical level in dialogue committees rather than have it be, like, Donald Trump and somebody going at it on Twitter or in competing press statements,” said Dmitry Grozoubinski, a former trade diplomat for the Australian government and the founder of ExplainTrade, an outlet based in Geneva.

The Commission responded with characteristic restraint after Trump threatened retaliation over the latest Google fine. After the U.S. president’s Truth Social post, Brussels emphasized it would seek “technical-level contact” between the EU and the U.S., said deputy chief spokesperson Olof Gill. A meeting at a higher, political level hasn’t yet been confirmed.

However, several people familiar with the matter confirmed they were expecting a reaction from the U.S., possibly in the form of a new 301 investigation.

“I have not heard anything yet on timing for the launch or scope of the Section 301 investigation,” said a U.S. tech industry representative, who was granted anonymity to discuss the conversations with administration officials. “But I believe this has been in the works for some time as a means of leverage in U.S. negotiations with the EU.”

Europe’s strategy depends on shifting disputes out of Trump’s preferred arena of public confrontation. But officials acknowledge that this bet rests on one unpredictable factor: Trump himself.

“We cannot let our guard down,” another Commission official said. “Trump may change course at any moment. His focus is on how markets react to his policies, not on how the EU behaves.”

Stefanie Bolzen reported from Washington and Camille Gijs reported from Brussels. Oliver Ward contributed to this report.