In Tax Overhaul, Trump Tries to Defy the Economic Odds

When President Trump adds his distinctive signature to the tax bill, he will also be making a huge bet that the Republican strategy of deep cuts for businesses and wealthy individuals will fuel extraordinary growth across the board.

Perhaps more than any other American political leader, Mr. Trump knows that long shots, like his own presidential bid, sometimes pay off. In that vein, he and congressional Republicans are arguing that their bitterly contested and expensive rewrite of the tax code will ultimately create more jobs and raise wages.

If they are proved correct, they will be repudiating not only historical experience, but most experts. From Congress’s own prognosticators to Wall Street’s virtuosos, scarcely any independent analyses project anything like the rosy forecasts offered by the president’s top economic advisers.

To Mr. Trump and his allies, the normal models just do not fully capture the high-octane “rocket fuel” embedded in the tax plan. Mr. Trump intuitively understands just how much attitudes and expectations can shape economic decisions.

With a businessman in the White House, Mr. Trump argues that companies, large and small, have a renewed faith in the economy. And the corporate tax cut, combined with the rollback in regulation, will prompt waves of new investment and hiring, as middle-class Americans liberally spend the extra money in their pockets.

“We’re going to easily see 4 percent growth next year,” the National Economic Council director, Gary D. Cohn, said. Steven Mnuchin, the Treasury secretary, declared the tax plan would generate enough growth to more than pay for its $1.5 trillion cost.

But those pronouncements are at odds with estimates from the former employer of both men, Goldman Sachs. The bank projected that the tax bill will add just three-tenths of 1 percent of growth in the next two years, before its impact peters out.

The firm’s annual growth estimate of 2.5 percent for 2018 matched the one issued this week by the nation’s central bank, the Federal Reserve, while the latest median Wall Street forecast hovered close by. And in 2019, growth is expected to drop to 1.8 percent, Alec Phillips, chief United States political economist for Goldman, said Wednesday after the Senate vote.

“We note that the effect in 2020 and beyond looks minimal and could actually be slightly negative,” the company said in a recent published summary.

Such projections are unlikely to deter Mr. Trump and Republican leaders from declaring success next year. Lower taxes and extra incentives to invest in 2018 are almost certain to encourage consumers to spend and businesses to expand.

Reduced rates mean most Americans will start taking home more money right away. Roughly three-quarters of taxpayers are expected to get a cut next year, according to the nonpartisan Tax Policy Center.

Employers may offer other sweeteners, even if they were not specifically spurred by the tax plan. AT&T announced Wednesday that it was giving more than 200,000 domestic employees a $1,000 bonus when the tax bill is signed. Fifth Third Bancorp, based in Cincinnati, also promised a $1,000 bonus and said it would raise the company’s minimum wage to $15 an hour.