Japan minister says fiscal plans will boost yen long term

The US Treasury's decision to join the Bank of Japan in a coordinated yen-buying intervention — the first such joint operation since 2011 — has stabilized the Japanese currency in the short term, but analysts warn that lasting relief will require deeper economic shifts rather than market firepower alone.

A Rare and Historic Move

Japan and the United States confirmed on August 1 that they had jointly intervened in currency markets to halt the yen's slide to 40-year lows against the dollar. Central bank data indicated Japan may have spent as much as $36.58 billion buying yen during the operation. The intervention came after the yen weakened past levels not seen since 1986, prompting US Treasury Secretary Scott Bessent to prepare purchases of between $5 billion and $10 billion worth of yen.reuters+3

The move marked the first coordinated currency intervention between the two countries in 15 years, according to Goldman Sachs ↘ 0.23% analysts. Japan's Finance Ministry said the action "countered excessive volatility and disorderly movements in the Japanese yen in recent months".aljazeera+1

US Self-Interest Drove Participation

The US Treasury's involvement was rooted in market stability rather than altruism, according to Michael Diamantopoulos, an associate director for fixed income and currency at Morningstar ↗ 0.03%. "If Japan were forced to continue defending its currency entirely on its own, it might need to liquidate substantial holdings of US Treasury securities from its official foreign reserves," he explained. "Large-scale sales of US sovereign debt could push US yields higher and destabilize broader treasury and funding markets".global.morningstar

By participating and selling euro reserves to buy yen, the US helped support the currency while avoiding direct pressure on US Treasury markets.global.morningstar

A Temporary Fix at Best

Analysts broadly view the intervention as a stopgap. "The primary objective of this joint action is to stop or slow down the pace of yen depreciation, rather than engineer an outright reversal of the currency's overall trajectory," Diamantopoulos said. "Lasting stability in the exchange rate will ultimately require further convergence in real interest rates and broader structural macroeconomic adjustments".global.morningstar

The yen is weakening for fundamental reasons: even as the Bank of Japan has begun nudging rates higher, Japanese real yields remain well below those of major global peers, creating incentives for capital to flow elsewhere.global.morningstar

Japan's Growth Strategy Minister Minoru Kiuchi pushed back on Monday against the bearish narrative, telling Bloomberg Television that Japan's spending and investment plans would provide a long-term boost for the yen. "Japanese fiscal policy is not so expansionary as you think, because we put great importance on sustainability," Kiuchi said.bloomberg

Whether fiscal promises can accomplish what $36 billion in intervention spending could not remains the central question facing the USD/JPY market in the weeks ahead.