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Although businesses could invest more, economists say, a vicious cycle of lackluster economic growth and stop-and-go consumer spending patterns gives them little incentive. Many corporations instead are investing in emerging countries such as China, where they see potential for stronger growth.

A big exception to anemic business investment is one that Mr. Reinhart cites as a reason for optimism. That is the robust growth from oil companies since the discovery in the past decade of new ways to extract large quantities of oil and natural gas from shale bedrock in the American heartland.

“We are reluctant to discount the dynamism of the U.S. economy” entirely, Mr. Reinhart said, noting that the oil and gas sector has accounted for nearly a quarter of all investment in structures recently, demonstrating how American businesses can unleash world-changing innovation when they are motivated to do so.

The shale revolution, moreover, is prompting other industries such as chemicals and plastics to invest in new plants in drilling areas to take advantage of the relatively low-cost energy, he said.