Greenhouse gas emissions have also been curbed because natural gas, when used as an alternative to coal to generate electricity, produces about half as much carbon dioxide.
Finally, fracking and horizontal drilling have been applied to oil, spawning a parallel boom. In 2012, U.S. oil production is up 25 percent from 2008.
That's about another 400,000 production and supplier jobs, estimates the consulting firm IHS.
The complaint that LNG exports might unwisely drive up natural gas prices comes from politicians and gas consumers.
Sen. Ron Wyden, D-Ore., argues the Obama administration should ensure that "unfettered natural gas exports don't harm U.S. consumers and manufacturers."
Dow Chemical says a "rush to export liquefied natural gas" could jeopardize the "tremendous competitive advantage for American industry" from low-price shale gas.
In theory, LNG might divert large volumes of natural gas because the wellhead price of U.S. gas is, on an energy-equivalent basis, much cheaper than oil.
But in practice, this isn't likely: LNG isn't easily substituted for oil and is costly. The expense of liquefying it to minus-260 degrees Fahrenheit and transporting it long distances in refrigerator tankers raises the price sharply.
LNG projects are fabulously expensive. Sabine Pass in Louisiana, a project approved by the Department of Energy, will cost $11 billion and could provide customers in Britain, South Korea, India and Spain with gas equal to about 3 percent of present U.S. supply.
Exporting natural gas simply isn't as easy as exporting wheat. Unsurprisingly, LNG satisfied less than 10 percent of global gas demand in 2010.
Nor are American producers guaranteed contracts. Other suppliers (Qatar, Australia) might undercut U.S. prices. But the global LNG market could absorb some American shale-gas production.
Why discourage this? A study commissioned by the Department of Energy suggests that the price impact would be modest.
The truth is that the United States needs domestic and foreign buyers for its natural gas.
Supply is outpacing demand, leading to a collapse in prices and drilling. Gas rigs are down half from a year ago, reports the energy firm Baker Hughes.
Prices can't be held at artificially low levels. Companies won't drill unless they can profitably sell what they find.
A policy that discriminates against producers in favor of consumers by restricting foreign sales will hurt both. The gas boom will recede as an engine of growth.
For years, Americans have complained about trade deficits. Now that we have something more to sell, we shouldn't turn away customers.