President Trump’s trade ambassador, Jamieson Greer, was in the hot seat on Tuesday as senators of both parties demanded answers about the administration’s use of tariffs that have roiled markets and spooked allies. One Republican senator said he would have to “choke” someone if a successful strategy isn’t laid out soon. 

Mr. Greer is just the latest administration official to try and explain the broader goals behind the massive tariff increases. Secretary Bessent and the director of the National Economic Council, Kevin Hassett, have been asserting that negotiations with individual countries is the ultimate objective, though hardliners like Mr. Greer and trade advisor Peter Navarro have said this is much bigger than a simple negotiation. 

Fresh fears in the markets arose on Tuesday when the White House press secretary, Karoline Leavitt, confirmed that American tariffs on Chinese goods would reach 104 percent at the beginning of the day on Wednesday. As Ms. Leavitt was speaking from the podium, the Dow dropped more than 300 points. 

Mr. Trump made the decision to slap China with a 50 percent tariff on top of the existing 54 percent tax after the Chinese hit America with a 34 percent import tax following Mr. Trump’s “Liberation Day” tariffs. 

“It was a mistake for China to retaliate,” the press secretary said during the briefing. 

“When America is punched, he punches back harder. That’s why there will be 104 percent tariffs going into effect on China tonight at midnight,” Ms. Leavitt said. 

Senator Tillis has been demanding answers about the tariff strategy for days, and decided to vent his frustrations at the hearing on Tuesday. 

“Whose throat do I get to choke if this proves to be wrong?” Mr. Tillis asked Mr. Greer. “It seems like we’ve decided to begin a trade war on all fronts, and that’s okay if the person who thought this through has an answer for why you go after partners that we have a very long, storied relationship with. Maybe we give some developing countries a break.”

After questioning Mr. Greer, Mr. Tillis told the Sun that he did not get the clarity that he wanted from the hearing. 

“I’m looking for a process, and this is novel,” the North Carolina senator, who is in danger of losing re-election next year, told the Sun.

“When you implement a tariff regimen like this, having simultaneous negotiations, it’s just hard to get my head wrapped around how all this comes to a successful win,” Mr. Tillis added. 

Senator Lankford similarly pressed Mr. Greer about what his goals were. Mr. Navarro has asserted that countries must lower their tariffs and other trade barriers so that trade deficits are closed — something Mr. Lankford says is not realistic. 

“Do you have any timeline on certain countries or places that you have set internally to say, ‘We hope to have negotiations completed by this point?’” Mr. Lankford asked. 

“The trade deficit has been decades in the making and it’s not gonna be solved overnight,” Mr. Greer said in response while clarifying that the “outcome” was more important than an “artificial” timeline. 

“I don’t anticipate that we’re ever gonna have equal trade with Vietnam. We’re a much larger economy than they are,” Mr. Lankford said. “Most countries are never gonna buy as much as we’re purchasing because we just purchase a lot more.”

The top Democrat on the Finance Committee, Senator Wyden, said Tuesday that he would soon introduce a resolution to repeal Mr. Trump’s new global tariffs. A similar measure to rescind the Canadian tariffs passed through the chamber last week with four Republican supporters, and Mr. Wyden says his new resolution will also get GOP votes. 

The resolution was officially introduced Tuesday afternoon, with Senator Paul signing on as the Republican co-sponsor. 

After questioning Mr. Greer, Mr. Wyden told the Sun that the trade representative has no clue about the damage he is doing to small businesses and middle class families. 

“He has no sense of urgency for the people that are hurting — the small businesses and the people who are worried about their 401k’s,” Mr. Wyden said. “He just seems to think someday everything’s gonna be unicorns and happiness.”

Mr. Trump said during an Oval Office press event on Monday that some of the tariffs may be permanent, though others may be just negotiating tools. 

“It can both be true. There can be permanent tariffs and there could also be negotiations because there are things that we need beyond tariffs,” the president told reporters. When a member of the press corps told him that it would “take time” to increase manufacturing here at home, Mr. Trump shot back: “Of course it takes time.” 

“Are you asking me a question or are you telling me? Yeah, it takes time. You gotta build a thing called a factory. You gotta build your energy. You gotta do a lot of things,” Mr. Trump said.