Japanese Bond Market Warns of Fiscal Expansion Risks

Japan's bond market is sending warning signals as the government pursues fiscal expansion. The country's public debt remains above 200% of GDP, and although it's expected to decline gradually under current assumptions, rising interest rates are changing the calculation at the margin.

The BOJ controls the overnight policy rate but doesn't directly control the 30-year yield. A recent 25-basis-point rate increase to 1.25% is significant because it signals a move away from emergency monetary settings, but the rise in ultra-long yields reflects investors reassessing the long-term price of carrying Japanese fiscal and inflation risk.

The 30-year bond essentially asks what return an investor should demand today to lend money to Japan for three decades. The answer is increasingly higher. This market warning label on government spending suggests a debt-servicing problem that won't arrive overnight, but will eventually become more pressing.