Debt as a blessing: A capital screening mechanism

F Feng Dong (BLSA-ZJU Research Center and Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.) T Thomas J. Sargent (Department of Economics, New York University) P Pengfei Wang (Key Laboratory of Photochemical Conversion and Optoelectronic Materials) Y Yizhen Wang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University)

Abstract

We challenge a recently popular view that a negative interest-growth rate gap ( r < g ) offers a “free lunch” for debt-financed government spending by formulating a model in which r and g are endogenous variables shaped by fiscal policy through its effects on equilibrium multiplicity and capital allocation. Observing r < g can signal that sustained government deficits have generated multiple steady states, and the economy has converged to a stable low-efficiency equilibrium. With its heterogeneous entrepreneurs, the model’s real interest rate serves as a screening device for investment efficiency. Causation runs from the fiscal regime to equilibrium selection and outcomes: Fiscal surpluses eliminate equilibrium multiplicity and anchor expectations that sustain a unique, high-productivity equilibrium, thereby rationalizing Alexander Hamilton’s characterization of “debt as a blessing.” Persistent deficits can push the economy into a “misallocation trap” characterized by scarce safe assets, low interest rates, survival of inefficient firms, depressed aggregate productivity, and self-validating low growth. Thus, costs of debt-financed fiscal deficits consist not only of deferred taxes, but also of permanently lower national productive capacity.

Article Details

Volume / Issue Vol. 123, Issue 27
Published July 07, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (4)

F

Feng Dong

BLSA-ZJU Research Center and Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.

T

Thomas J. Sargent

Department of Economics, New York University

P

Pengfei Wang

Key Laboratory of Photochemical Conversion and Optoelectronic Materials

Y

Yizhen Wang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University