Americans' evaluations of current U.S. economic conditions and the economy's trajectory are the most optimistic in nearly two decades, Gallup reported.

Currently, 54% of Americans rate economic conditions as "excellent" or "good," and just 12% as "poor," Gallup reported.

Also, by 57% to 34%, more Americans say the economy is getting better than say it is getting worse.

The combination of those answers results in a Gallup Economic Confidence Index of +33. The index was last at that level in January 2004, and has not been higher since November 2000 (+39), at the tail end of the dot-com boom.

To be sure, National Economic Council Director Larry Kudlow says “enormous confidence” just one of the many factors driving robust economic growth, which he doesn’t expect to stop anytime soon.

“I'll start with the enormous confidence that you see in the country. That's very important. People are moving, they're working, they're investing. We haven’t had that in a long time,” the veteran financial guru and former Ronald Reagan adviser told Bloomberg Television.

“President Trump is a growth guy and he has launched a boom that nobody thought possible,” he said.

“I think a lot of folks are underestimating the power of lower marginal tax rates, typically on large and small business, and the deregulation program and the energy program that we've gone through and the president's view that business is good," said Kudlow, who worked as Reagan’s budget deputy between 1981 and 1985.

"There's no war against business people. Attitudes have changed and I think that amounts to a lot. We've never really seen this kind of confidence movement before,” said Kudlow, who served as the Trump campaign's senior economic adviser.

"We haven't had good, old-fashioned business investment" in years, Kudlow said. "You could probably go back to the year 2000. So it's been a long time," he said.

"My point is we're in an economic boom. Frankly, most folks thought it was impossible. Frankly, it's happened. So last question. It's a great blessing. Prosperity is a good thing," Kudlow said.

• Kudlow Sees 'Enormous Confidence' Driving US Economic Growth
• Kudlow: Trump's Economic Boom Can Last 'A Good Many Years'