Our world has been upended.
U.S. oil and natural gas imports are falling. Cheaper energy is helping U.S. manufacturing, especially petrochemical plants using natural gas as an input. By one (industry-financed) study, the oil and gas boom and its side effects have added 1.7 million jobs.
To be sure, fracking raises environmental concerns, mainly involving the disposal of wastewater. Indeed, Mitchell advocated "sensible" regulation of these side effects (also, interestingly, his family foundation has focused on coping with global warming). But whatever shale gas' drawbacks, they are dwarfed by the benefits.
It's been argued - mainly by the Breakthrough Institute, a think tank - that Mitchell's role is overblown and that federal-research advances into "geologic mapping," fracking and horizontal drilling underpinned his success.
These helped, but the argument's weakness is that the same information and technologies were available to other oil companies, including better-financed "majors" (ExxonMobil, Chevron and the like), and none managed his feat.
In truth, most "experts" considered what Mitchell did to be impossible. This included much of his staff.
"My engineers kept telling me, 'You are wasting your money, Mitchell,' " he recalled to Forbes in 2009.
These narratives are worth retelling because they illuminate some bedrock sources of economic growth, jobs and higher living standards.
In 2012, Mitchell ranked 239th on Forbes' list of the 400 wealthiest Americans with a net worth of $2 billion.
It's fashionable these days to disparage the top 1 percent as being "filthy rich" and, symbolized by Wall Street traders and hedge-fund operators, not contributing much to the common welfare
Whatever the truth of this stereotype, Mitchell's life reminds us that many of the super-wealthy came by their fortunes the old-fashioned way: through patient risk-taking that also created huge social and economic benefits.
Part of our problem today is that we don't have enough of this.