Once upon a time, shale gas amounted to 2% of U.S. natural gas production. Believe it or not, that day and age was just 10 years ago.

Today, shale gas is nearly 40% of America’s total natural gas production, a figure that keeps rising with each passing month. The effects of this completely unforeseen development are at the heart of Charles Morris’s new book, Comeback: America’s New Economic Boom, which Daniel Yergin reviewed this weekend in the Wall Street Journal.

According to Yergin, Morris’s primary focus is the resurgent U.S. economy:

“… the United States is on the threshold of a long-term economic boom, one that could rival the 1950s-’60s era of industrial dominance.”

Rising American productivity, industrial restructuring, logistical advantages – many factors are propelling this economic boom, but the one Morris singles out in Comeback is “the new X-factor, the American energy advantage.”

“As Mr. Morris puts it, shale gas can be the central pillar of America’s coming economic rebound. ‘Unless something goes horribly wrong,’ he says, ‘energy is a game changer.’ The U.S. and Canada have this ace up their sleeves while, at least at this point, no one else does.”

The members of the Pickens Plan Army know this point by heart. For the past five years, Boone Pickens has insisted that the current energy revolution could jumpstart the U.S. economy. Facts and figures in support of this point are detailed again and again in Comeback:

Shale gas has led to the creation of 1.7 million jobs since 2008. Meanwhile, other sectors tanked as the Great Recession throttled the U.S. economy. By 2020, shale gas will lead to the creation of 4 million jobs.

The complete review of Comeback is available at the Wall Street Journal website. (Subscription may be required.)