James Livingston: It’s Consumer Spending, Stupid

James Livingston, a professor of history at Rutgers, is the author of “Against Thrift: Why Consumer Culture Is Good for the Economy, the Environment and Your Soul.”

AS an economic historian who has been studying American capitalism for 35 years, I’m going to let you in on the best-kept secret of the last century: private investment — that is, using business profits to increase productivity and output — doesn’t actually drive economic growth. Consumer debt and government spending do. Private investment isn’t even necessary to promote growth....

Between 1900 and 2000, real gross domestic product per capita (the output of goods and services per person) grew more than 600 percent. Meanwhile, net business investment declined 70 percent as a share of G.D.P. What’s more, in 1900 almost all investment came from the private sector — from companies, not from government — whereas in 2000, most investment was either from government spending (out of tax revenues) or “residential investment,” which means consumer spending on housing, rather than business expenditure on plants, equipment and labor.

In other words, over the course of the last century, net business investment atrophied while G.D.P. per capita increased spectacularly. And the source of that growth? Increased consumer spending, coupled with and amplified by government outlays....