Last week Peter Coy wrote at Bloomberg, in "How to Pull the World Economy Out of Its Rut," about economist Larry Summers' argument that we need massive public investment. Coy writes that Summers has been "jetting around the world" trying to convince central bankers "to reach out to the governments they work for … and insist on strong fiscal stimulus in the form of infrastructure spending and the like." (i.e. "Public investment".)

The case for this is very, very strong. Never mind that around the world infrastructure is crumbling. Just doing the basic job of government and making sure that things like infrastructure are up to par has fallen out of favor among the world's elites, because "government spending." Summers makes a different argument about why public investment – government spending on things countries and people and economies need – is essential to keep the world's economy going.

Coy writes, "Summers's deeper argument is that world growth is stuck in a rut because there's a chronic shortage of demand for goods and services and a concomitant excess of desired savings."