How Japan Could Accidentally Crash Global Markets

For thirty years, the world learned how to borrow Japan’s money. Now Japan is changing the price. Japan spent decades fighting deflation with zero interest rates, quantitative easing, and eventually negative rates. The unintended result was much bigger than Japan itself: the yen became one of the world’s cheapest funding currencies, Japanese savings flowed into foreign assets, and global investors built enormous leveraged trades around the assumption that Japanese money would remain cheap. Now inflation, a weak yen, expensive energy, and Bank of Japan interest-rate hikes are threatening that assumption. In this episode of The Financial Historian, we break down the yen carry trade, Japan’s role in global capital markets, its massive holdings of U.S. Treasuries, and why even a seemingly tiny Japanese rate hike could trigger forced selling far beyond Tokyo. Japan does not need to deliberately crash global markets. It only needs to make Japanese money normal again. Key Facts & Insights • After Japan’s historic asset bubble collapsed in the early 1990s, the Bank of Japan spent decades pushing interest rates toward zero—and eventually below zero—in an effort to defeat deflation and revive economic growth. • Those ultra-low Japanese interest rates helped create the yen carry trade: investors borrow or obtain financing in cheap yen and invest the proceeds in higher-yielding foreign bonds, stocks, currencies, and other global assets. • The true size of the yen carry trade is impossible to measure precisely because much of the exposure sits inside derivatives, foreign-exchange swaps, forwards, and leveraged institutional portfolios rather than simple bank loans. • On August 5, 2024, Japan’s Nikkei 225 plunged 12.4% in a single trading session, its worst percentage decline since Black Monday in 1987. A rapidly strengthening yen and the unwinding of leveraged carry trades helped amplify the global market selloff. • Japan is now moving away from the monetary regime that made the carry trade so attractive. The Bank of Japan raised its policy rate to 1% in June 2026, its highest level in roughly three decades, while markets increasingly expect additional monetary tightening. • Japan spent roughly $96.5 billion between late July and late August 2026 intervening in foreign-exchange markets to support the yen—evidence of how difficult the country’s currency problem has become. • The risk extends beyond hedge funds. Japanese pension funds, insurers, banks, and institutional investors accumulated enormous foreign portfolios during decades when domestic Japanese bonds offered almost no return. As Japanese bond yields rise, keeping more capital at home becomes increasingly attractive. • Japan does not need to suddenly dump foreign assets to move global bond markets. If Japanese investors simply become less willing to finance new U.S. government debt, the effect could appear through higher Treasury yields, more expensive mortgages and corporate borrowing, and lower valuations for risk assets. Further Reading • The Holy Grail of Macroeconomics: Lessons from Japan’s Great Recession — Richard C. Koo — A fascinating explanation of what happened after Japan’s asset bubble collapsed, and why conventional monetary policy struggled to restart the economy. • Princes of the Yen — Richard A. Werner — A provocative exploration of the Bank of Japan, credit creation, monetary policy, and the financial forces behind Japan’s extraordinary boom and bust. • The Price of Time: The Real Story of Interest — Edward Chancellor — An excellent broader history of interest rates and what happens when societies become accustomed to unusually cheap capital. #JapanEconomy #YenCarryTrade #JapaneseYen #BankOfJapan #InterestRates #GlobalMarkets #StockMarket #MarketCrash #CarryTrade #USTreasuries #BondMarket #MonetaryPolicy #GlobalEconomy #FinancialMarkets #FinancialHistory #FinanceExplained #HowMoneyWorks #EconomicHistory #CurrencyMarkets #financialhistorian If this gave you a new perspective, hit subscribe. History has the answers—and I’ll show you where to look. 0:00 The Yen's Unprecedented Crisis 1:25 The Origins of the Great Bubble 3:17 The Mechanics of the Yen Carry Trade 5:53 When the Feedback Loop Collides 10:05 The Shift in Global Capital Flows