President Trump pushed Congress to pass a still-forming tax reform bill in his first speech on the topic in Missouri on Wednesday afternoon, warning Republican lawmakers not to disappoint him this time around.

“I don’t want to be disappointed by Congress, do you understand me?” Trump said, pointing into a crowd that included much of the state’s GOP congressional delegation. “Do you understand?”

“I think Congress is going to make a comeback,” the president added. “I hope so.”

Trump also directly called out Missouri’s Democratic senator, Claire McCaskill, who is facing a tough 2018 reelection bid in a state that voted solidly for Trump last year. The president said she must back the tax reform plan or face punishment at the ballot box.

“Your senator, Claire McCaskill, she must do this for you, and if she doesn’t do this for you, you have to vote her out of office,” Trump said. “She’s got to make that commitment.”

The president appeared far more comfortable talking about tax policy than health care reform, which he never gave a major speech about as Congress struggled and ultimately failed to repeal Obamacare. He also largely stuck to his prepared remarks, staying on message for the entire speech and refraining from criticizing any lawmakers from his own party by name. That marks a contrast from his many Twitter jabs at Republican senators over the past two weeks and his insult of Sen. Jeff Flake, R-Ariz., during a freewheeling campaign rally in Phoenix last week.

President Trump speaks about tax reform Wednesday at the Loren Cook Company in Springfield, Mo. (Photo: Alex Brandon/AP)

Many details of the future tax reform plan remain unclear, with congressional Republicans divided over the key issue of whether tax cuts need to be offset by spending cuts or other measures to maintain deficit neutrality. Trump didn’t mention offsets in the broad outlines of a tax plan Wednesday. His plan includes lowering the corporate tax rate from 40 percent to 15 percent, allowing corporations to bring back trillions of dollars from overseas, lowering tax rates for individuals and simplifying the tax code.

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Trump made a populist pitch for his plan, saying the current tax code is “unfair” and privileges the wealthiest Americans, who can hire accountants to exploit loopholes. He suggested that his plan would be harder on wealthier people like himself. “Maybe we shouldn’t be doing this, you know?” Trump joked about the plan’s potential effect on his personal fortune. “But we’re doing the right thing.”

But tax policy experts say the White House’s plan so far would lower taxes for higher earners, according to Bloomberg, and Democrats are already calling it “Robin Hood in reverse.”

Mark Meckler, the president of Citizens for Self Governance and a co-founder of the Tea Party, said he believed Trump was right to put the “burden” on Congress when it comes to tax reform. He added that he hopes the president and Congress come around to making the plan deficit-neutral. “If they’re going to issue tax cuts, they have to cut spending,” Meckler said. “I don’t believe the American people will find [tax cuts without spending cuts] acceptable, and I think he will find himself at odds with the American people.”

The Trump administration has pushed for Congress to pass the plan by the end of the year, but has recently softened that expectation. Senate Majority Leader Mitch McConnell complained over the August recess that the president has “excessive expectations” for Congress, particularly around the speed with which they can push through legislation. And Congress must pass key appropriations bills, send relief to the victims of Tropical Storm Harvey and lift the debt ceiling this fall.

“Earlier in the year, I said I thought we’d get it done by August, and I was wrong, OK?” Treasury Secretary Steve Mnuchin told reporters Friday. “I am now going to say that I’m very hopeful and I think we can get this done by the end of the year, but we will continue to revisit that.”

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