Modern Monetary Theory (MMT)

Modern Monetary Theory: a revolution in macroeconomic thinking? Modern Monetary Theory (MMT) is an unorthodox macroeconomic theory that rethinks the role of government finances in countries with a sovereign currency. MMT challenges conventional wisdom about government debt, deficits, and monetary policy. For investors, understanding MMT is important regardless of agreement with its conclusions—MMT ideas increasingly influence policy debates.

Key tenets of MMT

Sovereign currency issuer: a country that issues its own freely-floating currency (the USA, Japan, UK) technically cannot “go bankrupt” on debts denominated in that currency. The central bank can always create money to service the debt. This is fundamentally different from households or businesses, which must first earn or borrow money.

Taxes do not finance spending: in the MMT framework, the government spends first (creates money), then collects taxes (destroys money). Taxes are not needed for financing, but to: create demand for the currency (taxes must be paid in the national currency), control inflation (removal of excess purchasing power), redistribution (social justice).

Real constraints: the limitation to government spending is not financial, but the real capacity of the economy. If spending exceeds productive potential—inflation arises. Inflation, not default, is the real constraint for a sovereign issuer.

Functional Finance: fiscal policy should be evaluated by its functional results (full employment, price stability), not by accounting indicators (size of deficit, debt-to-GDP).

Job Guarantee

The central policy proposal of MMT is the Job Guarantee (JG): the government acts as “employer of last resort,” offering jobs at a fixed rate to all willing workers. The JG serves as an automatic stabilizer: in recession, employment in JG grows (counter-cyclical spending), in boom—it shrinks (workers move to the private sector).

JG anchors wages: the fixed rate in JG establishes an effective minimum wage in the economy. This differs from the Phillips Curve approach, where unemployment is used to control inflation.

Criticism of MMT

Inflationary risks: critics argue that MMT underestimates the inflationary risks of expansionary fiscal policy. Political incentives favor spending, cuts are more difficult. “Printing money” to finance deficits has historically led to hyperinflation (Weimar, Zimbabwe, Venezuela).

Credibility and confidence: even if technically the sovereign cannot default, loss of investor confidence in the currency can lead to capital flight, currency collapse, imported inflation. Argentina, Turkey demonstrate that “sovereign” does not mean “unlimited.”

International constraints: the MMT framework works better for reserve currencies (USD). For emerging markets with foreign-denominated debt and dependence on imports constraints are more binding.

Operational challenges: timing fiscal adjustments is difficult. The political process is slow. Fine-tuning the economy through fiscal policy may be destabilizing.

MMT in practice

COVID-19 response in many countries resembled MMT prescriptions: massive fiscal expansion, financed by the central bank (QE). Result: recovery without immediate inflation (although 2021-2022 showed delayed effects). Japan is often cited as a “natural experiment” for MMT: massive debt/GDP, low rates, no default. But also decades of low growth, aging population.

Implications for investors

Regardless of the validity of MMT, its ideas influence policy. Greater tolerance of deficits means potentially larger fiscal stimulus in recessions. This may be positive for risky assets. But also higher long-term inflation risks, which affects bond valuations.

Currency implications: aggressive MMT-style policies may undermine confidence in the currency. Diversification into hard assets, foreign currencies may serve as a hedge.