Representative Adam Kinzinger, an Illinois Republican, said passing tax legislation would be more difficult than overhauling health care, requiring a compromise between the plans proposed by Congress and the White House.

“Of course the White House is going to have their view of it,” he said Wednesday on MSNBC. “The two will get married together at some point. It probably won’t look like either of ours in total but hopefully it will be something that will put a little jet fuel in the economy.”

Three Years

For cuts of the size Trump envisions, that most likely means they’d have to be temporary, and perhaps very short-lived. On Tuesday, the congressional Joint Committee on Taxation said in a letter to Ryan that a corporate tax rate of 20 percent -- five percentage points higher than Trump has proposed -- would create deficits in the long run even if it remained in effect for just three years.

Foreshadowing that finding, Ryan’s chief tax counsel, George Callas, told a banking conference in Washington last week that Congress might have to limit a corporate tax rate cut to just two years -- if it was part of a plan that didn’t achieve revenue neutrality.

Such a temporary cut would have no effect on business decisions, he said. “It would not cause anyone to build a factory,” he said. “It would not cause anyone to restructure their supply chain.”

It wouldn’t even cause much joy in corporate America, said Albert Liguori, an international tax lawyer and managing director at corporate strategy and turnaround firm Alvarez & Marsal.

“Businesses would rather see the certainty of permanency and be more certain that a tax bill will be passed,” Liguori said. “The 20 percent range -- companies would be more than happy with that because it’s reliably in line with other countries.”

Dynamic Scoring

Mnuchin has said that Trump’s tax cuts would be revenue neutral -- in part because they’d lead to rapid economic growth that would help boost federal revenue. Trump would use such dynamic scoring -- that is, accounting for economic changes caused by his plan -- to evaluate the revenue effects, Mnuchin said. But even with resulting growth, economists of all stripes say there’s little chance that Trump’s proposed 15 percent rate, absent the $1.1 trillion that BAT would raise to underwrite rate cuts, could be revenue neutral.