CHARLESTON, W.Va. -- The nature of work keeps evolving in the automated Computer Age. Productivity per employee keeps rising. The Wall Street Journal reported last week that average business revenue per worker at S&P 500 companies jumped from $378,000 in 2007 to $420,000 in 2011. Corporate profits boom while employee salaries lag.

Conservative columnist David Brooks says the U.S. economy is splitting into two sectors: Highly profitable international firms selling in global competition -- and less-lucrative, home-oriented occupations such as health care, education and government, "the less-tradable economy where more Americans actually live."

The world-market sector is booming because of several factors, he said. "First, smart machines. ... We are moving to an age of quiet factories, with more robots and better software. That reduces the importance of wage rates. It boosts U.S. companies that make software and smart machines." The grim trend: better machines, fewer workers.

Another factor is the shale oil and gas revolution wrought by fracking and horizontal drilling, Brooks wrote. Soon it will enable America to export energy in great quantities. Also, middle classes are growing in many developing nations, creating ever-bigger markets for U.S. products.

To compete in the global marketplace, America's exporting corporations "have become relentlessly dynamic and very (sometimes brutally) efficient," he said. Employee needs matter less than "enormous profits" available in big-time commerce.

Politically, Brooks offered this analysis:

"Republicans often live in and love the efficient globalized sector and believe it should be a model for the entire society. ... Democrats are more likely to live in and respect the values of the second [home-oriented service] sector. They emphasize the destructive side of Economy I streamlining -- the huge profits at the top and the stagnant wages at the middle."

This seems to be an accurate picture of America's work trends. It's a shame that employees and their families are downgraded in the ruthless pursuit of more mechanized output and higher profits.

We've always felt that the economy is a terrible, unstoppable Juggernaut that hurts many and enriches others as it constantly changes. We hope Democrats can impose humane protections to aid average families while dog-eat-dog global competition surges.