The Bank of Japan has finally done what many thought impossible: it raised interest rates to a 31-year high, sending shockwaves through global markets. For years, Japan has been the odd one out in the global economy, the central bank that stubbornly clung to negative rates while others tightened. But today, Governor Ueda has turned the page, and the consequences will be felt from Wall Street to the City of London.
The yen, that perennial underperformer, has surged, punishing carry traders who borrowed cheaply in Tokyo to chase yield elsewhere. The carry trade, long a reliable source of returns, is now unwinding with the force of a tidal wave. Expect margin calls and a scramble for liquidity. The Nikkei 225, which had been on a tear, is now in retreat. Japanese equities, long buoyed by a weak currency and accommodative policy, face a reality check.
What forced the BOJ’s hand? Inflation, of course. After decades of deflation, Japan finally has price pressures, but this is no gentle warmth; it’s a fever. Core CPI has been above target for months, and the yen’s weakness was importing inflation. The BOJ had to act, but at what cost? The bond market is already convulsing. Japanese government bond yields are spiking, and with them, the cost of servicing Japan’s colossal debt. The Ministry of Finance will be sweating, for every percentage point increase in yields adds billions to the interest bill.
Global markets are bracing. The end of Japan’s ultra-loose policy means one of the last sources of cheap money is drying up. For decades, Japanese investors have bought foreign bonds, suppressing yields everywhere. That flow is now at risk of reversing. Imagine the world’s biggest creditor nation becoming a buyer of its own debt. The implications are staggering: higher yields globally, tighter financial conditions, and a potential squeeze on risk assets.
Central banks in the West may find their job harder. The Federal Reserve and the ECB are already fighting inflation, and a stronger yen and tighter Japanese policy will amplify their tightening. Capital flight from Japan could strain emerging markets, which relied on Japanese carry trade flows. The ‘Japan premium’ that has distorted global finance for years is about to be repriced.
For the UK, the impact is twofold. First, gilt yields are likely to rise in sympathy. Higher Japanese yields make UK debt less attractive, and the chancellor’s fiscal headroom, already wafer-thin, will shrink further. Second, the yen’s strength will hurt UK exporters who compete with Japanese firms. British carmakers and electronics companies will face a tougher market.
The bottom line: this is a regime change. The BOJ has broken its addiction to easy money, and the global economy must now navigate withdrawal symptoms. Markets that have become numb to Japanese exceptionalism will be in for a rude awakening. The question is not whether this will cause volatility, but how much damage it will do before the new equilibrium is found. As always, the market is a harsh teacher, and today, Japan has given us a painful lesson in the law of unintended consequences.









