A Number That Took Three Decades to Return
The Bank of Japan raised its short-term policy rate by 25 basis points on June 16, moving from 0.75% to 1%. The figure is modest by the standards of Western central banking. In the context of Japan’s monetary history, it is extraordinary. The last time Japanese rates sat at this level was 1995 — before the lost decade calcified into a structural condition, before deflation became the ambient threat that shaped every subsequent policy decision.
The BoJ did not arrive at 1% because Japan’s domestic economy generated the kind of demand-side inflation that textbook rate hikes are designed to cool. It arrived here because oil costs are rising at a pace that Japanese companies are passing on to each other — the BoJ’s own language — at a relatively fast rate. The source of that pass-through inflation is not domestic. It is the Iran war.
How 1% Became a 31-Year Record
Japan spent most of the period between 1999 and 2024 at or near zero, and briefly in negative territory after 2016. The entire edifice of Abenomics — the stimulus architecture that defined Japanese economic policy for over a decade — was premised on the assumption that deflation was the structural enemy and that near-zero rates were the permanent condition required to fight it.
That architecture has been dismantled not by a Japanese policy reversal but by an external shock. When conflict disrupts oil supply routes and drives up energy costs globally, import-dependent economies like Japan absorb the inflationary pressure with particular force. Japan imports roughly 90% of its energy. It has no meaningful domestic oil production. Every sustained increase in the global oil price is a tax on the Japanese economy levied by events happening thousands of miles away.
The BoJ’s rate decision is a rational response to a set of conditions the BoJ cannot control. That is the structural problem buried inside the policy announcement.
Bank of Japan Policy Rate (%)
Geopolitical Inflation and the Limits of Monetary Policy
Rate hikes work when inflation is generated by excess domestic demand or an overheated labor market. The mechanism is straightforward: raise the cost of borrowing, cool investment and consumption, reduce demand, reduce price pressure. The transmission is imperfect but directionally coherent.
Geopolitical inflation operates differently. When oil prices rise because a war is disrupting supply routes, a central bank raising rates does not reduce the price of oil. It does not end the war. It does not restore the disrupted supply chains. What it does is raise the cost of capital for Japanese businesses and households who are already absorbing higher energy costs — a compound pressure, not a remedy.
The BoJ is using a domestic instrument to manage an international problem. The instrument cannot reach the source of the problem. What it can do is signal to currency markets that Japan is willing to defend the yen’s purchasing power — which has been under sustained pressure — and attempt to prevent the inflationary pass-through from becoming entrenched in wage and price expectations.
Disruption to oil transit routes through the Persian Gulf has accelerated pass-through inflation across import-dependent economies, forcing central banks far from the conflict to respond.
Ojas Narappanawar / PexelsWhat Washington and London Are Not Doing
The contrast with the US Federal Reserve and the Bank of England is instructive. Both are expected to hold rates at their current levels. Both are also managing economies affected by Iran-war inflation. The decision not to move is itself a policy position — a judgment that domestic conditions do not yet require the additional tightening that Japan has now imposed on itself.
This divergence creates exchange rate dynamics that compound the original problem. If the Fed holds and the BoJ hikes, the interest rate differential narrows, which tends to support the yen against the dollar. A stronger yen reduces import costs — including oil — which partially offsets the inflationary pressure the hike was designed to address. The policy logic is circular in a way that reflects the fundamental constraint: no central bank can solve a geopolitical supply shock with interest rate policy alone.
The Price of a War You Did Not Choose
The BoJ’s decision encodes a geopolitical reality that monetary policy statements do not typically articulate. A country that has renounced offensive military capacity, that depends on US security guarantees, and that imports nearly all of its energy is structurally exposed to every significant conflict in the oil-producing world — regardless of its own foreign policy choices.
Japan’s 31-year rate record is not a story about Japanese economic success or failure. It is a story about how wars price themselves into economies that did not participate in them and cannot end them. The cost is distributed globally; the decision-making is concentrated among the parties with military skin in the game. That asymmetry between who pays and who decides is not a market inefficiency. It is the operating logic of the current international order.