While in a secular stagnation (Is the shorthand 'SecStag' catching on?), Samuelson and Scott suggest that constant or near-constant government budget deficits are needed to sustain an adequate level of demand to achieve full employment, as shown here:
|Samuelson and Scott (1971:437)|
The policy stance required during secular stagnation contrasts with the stance needed during periods of so-called "secular exhilaration" (with high demand), during which the right policy is running budget surpluses as a way to avoid overheating the economy and reduce inflationary pressures.
It's true that sustained deficits will increase public debt; however, the low cost of borrowing that usually comes with secular stagnation should help to ensure public debt levels won't get out of hand.
But hasn't the experience of Japan in the 1990s taught us that big deficits don't work to stimulate a stagnant economy, you might ask?
The answer is no. Kenneth Kuttner and Adam Posen demonstrated in "Passive Savers and Policy Effectiveness in Japan" that low tax revenues caused by a weak economy were to blame for the rising debt levels, not expansionary fiscal policy.
Of course, it's important that the spending be directed toward productive use.
I can think of two ways to achieve this goal. First, governments should invest in early childhood learning, an investment that's well known to pay-off in the long-run. Second, investing in infrastructure is also a good bet, as demonstrated several years ago by David Aschauer and Alicia Munnell, and as recently recommended by the IMF.
Aschauer, D., 1989, "Is Public Expenditure Productive", Journal of Monetary Economics, Vol. 23, pp. 177-200.
IMF, "Is it time for an infrastructure push? The macroeconomic effects of public investments", Chapter 3, October 2014.
Kuttner, K. and A. Posen, "Passive Savers and Policy Effectiveness in Japan", Institute for International Economics, 2001.
Munnell, A., 1990, "Why has productivity declined? Productivity and Public Investment" New England Economic Review, Federal Reserve Bank of Boston, January/February issue, pp. 3-22.
Samuelson and Scott, Economics, 3rd Canadian Edition, McGraw-Hill, 1971.