The trouble facing Reagan emulators is the U.S. is in a much different phase of the economic cycle than it was in 1981. The U.S. had just escaped a recession before Reagan took office and was about to enter another one that drove joblessness to 10.8 percent. That meant that GDP had a lot of room to run once it began to recover.

Fourth-Longest Expansion

The economy today is in its 90th month of an expansion that is already the fourth longest on record. At 4.6 percent, unemployment is at or below the lowest level many economists believe is maintainable in the long-run.

“The fact pattern is different now so the effect of any of the policies might well be different,” said Neal Soss, vice chairman at Credit Suisse Group AG in New York, who noted that most analysts reckon that the economic benefits of a Trump plan would be modest.

Besides, it wasn’t Reagan’s sweeping 1981 tax cuts that revved up the economy, he said. It was the lower interest rates engineered by Volcker after he broke the back of double-digit inflation.

“When the economy picked up at the end of 1982 the Fed had a lot to do with that by cutting rates in meaningful amounts,” said Soss, who served as an assistant to Volcker from 1980 to 1982.

The Fed now is hiking -- not cutting -- rates and is expected to tighten credit at its Dec. 13-14 meeting. Chair Janet Yellen has cautioned Trump and lawmakers against providing the economy with too much of a budgetary lift.

“In contrast to where the economy was after the financial crisis, when a large demand boost was needed to lower unemployment, we’re no longer in that state,” she told Congress’s Joint Economic Committee on Nov. 17.

Greenspan sees the U.S. heading toward stagflation -- a stagnant economy saddled with rising inflation -- though it may enjoy a “mild euphoria” first. “But unless we induce productivity to accelerate, the euphoria will be short-lived,” he said.

Spending Restraint