Manufacturing is booming again as the United States continues to lead the world in the production of goods. With just 4 percent of the world's population, the United States produces 21 percent of the world's goods.
That is well ahead of the 15 percent for China and 12 percent for Japan.
Manufactured goods account for 70 percent of U.S. exports.
But U.S. employment in manufacturing has declined.
Manufacturing has accounted for, on average, 13 percent of the U.S. economy since 1979 - but employment in that sector has fallen by an average of 250,000 jobs per year in that time, said the Kiplinger Letter.
Manufacturing employment fell from 16.6 million in October 2002 to under 12 million in October 2012.
That is because of mechanization. Manufacturers have turned to machines to increase productivity - just as coal companies replaced the pick and shovel.
Blue-collar jobs for high school graduates are giving way to jobs that require advanced technical skills or college degrees.