“Present-day Japan” from a Macroeconomic Perspective

Keynesian economics is a theory that originated primarily during times of “insufficient demand” (recession and unemployment) . However, present-day Japan faces constraints not from “demand” but from “supply capacity” (the ability to produce goods and services) .

1. The World Assumed by Keynesian Theory (The Principle of Effective Demand)

• Premise: A state where the world is flooded with unemployed workers and factory operating rates are low (meaning there is ample surplus supply capacity).
• Measures: By increasing aggregate demand (AD) through government spending to create jobs (fiscal stimulus) and lowering interest rates (monetary easing), employment and GDP can be expanded without causing a sharp rise in prices.

2. The Reality Facing Present-Day Japan (Supply-Side Shocks)

• Labor Shortage: Due to the structural issue of a declining birthrate and an aging population, the working-age population itself is shrinking. In other words, the economy is hitting the limits of labor supply.
• High Prices: Prices are rising not because domestic demand is robust (demand-pull inflation), but because raw material costs are being forced upward by a weak yen and high global resource prices (cost-push inflation).

3. The Core Problem: A Supply Shock, Not a Demand Slump

Today, the situation is the exact opposite. We are experiencing a supply-side crisis :

Cost-Push Inflation: Prices are not rising because consumers are spending eagerly. Instead, they are being pushed up by global resource costs and currency depreciation (like the weak Yen).

4. Why Traditional Keynesian Policies Backfire Now

Instead of creating growth, over-stimulating demand in a supply-constrained environment fuels the fire of inflation and weakens the local currency.

5. How Keynesian Theory Still Helps Us Today

Does this mean we should throw Keynes out the window? Not at all. Keynesian theory is still highly valuable, but as a framework for economic balance rather than just a tool for expansion.

• A Signal to Tighten: Keynesian economics isn’t just about spending money; it also dictates that when an economy is overheating or facing supply constraints, policymakers must pull back. The recent shifts by central banks toward raising interest rates are classic macroeconomic moves to curb excess pressure and stabilize the currency.
• Redefining “Good” Government Spending: Traditional Keynesian spending focused on creating generic jobs (like building infrastructure just to employ people). Today, government spending must pivot. Instead of creating more jobs, funding should focus on boosting productivity — investing in AI, automation, and digital transformation so fewer workers can produce more output.

The Verdict: Shifting from Demand to Supply

Keynesian theory isn’t dead; it is simply warning us that we are taking the wrong medicine for the current illness.

What modern economies facing labor shortages need right now is not demand stimulation, but Supply-Side Economics. The focus must shift toward structural reforms, deregulation, and technological innovation to expand our capacity to produce. Keynes helps us realize that before we try to make people buy more, we first need to figure out how to build more with less.