The Numbers Come First
The yen closed New York trading on Friday at 157.40 to the dollar, its strongest reading since early May. Just two days earlier it had been flirting with levels not seen since 1986. The reversal was not an accident.
Japan spent roughly ¥8.45 trillion — approximately $52.8 billion — buying yen on Thursday alone, according to data compiled by Bloomberg based on a comparison of Bank of Japan accounts and money brokers' forecasts. That figure, if confirmed, would represent the single largest one-day currency intervention in Tokyo's history.
The Federal Reserve Bank of New York sold euros to buy yen on behalf of the US Treasury Department on Friday, the Financial Times reported separately. At least two major US banks were asked by the New York Fed to check the yen-euro rate during the day, according to two people familiar with the matter who spoke to Bloomberg.
Bessent's Fingerprints Are on the Trade
Treasury Secretary Scott Bessent provided the verbal architecture for the move. In a Fox Business interview on Thursday, he said the yen is 'very undervalued' and that 'excess volatility' is not healthy. Reuters then published a photograph of a notepad in front of Bessent at a Camp David cabinet meeting. Under a 'To Do' heading, the note read: 'Buy Japanese Yen (JPY) $5-10 bil.'
Japanese Finance Minister Satsuki Katayama described Bessent as 'one of the most knowledgeable experts in markets.' Finance Ministry top currency official Atsushi Mimura said on Friday that Japan is receiving more than 'moral support' from Washington.
'Bessent's influence is significant,' said Nobuyasu Atago, chief economist at Rakuten Securities Economic Research Institute and a former BOJ official. 'The US is now becoming more cooperative with Japan's interventions.'
'The market had underestimated the authorities,' added Michiyoshi Kato, a senior adviser at Sumitomo Mitsui Trust Bank in Tokyo. 'It has likely become more difficult for speculators to sell the yen. If there is another intervention, the dollar-yen exchange rate will likely fall below 155 yen.'
The Strategic Logic Is Clear
The yen has been under pressure from rising oil prices, Japan's persistent budget deficits and a wide interest-rate gap with the US and other major economies. A continued slide carried two distinct risks for Washington: first, yen depreciation gives Japan a competitive trade advantage that would irritate President Donald Trump; second, if Tokyo were left to defend the yen alone, it might be forced to liquidate a portion of its substantial US Treasury holdings to fund further intervention — a move that would push American borrowing costs higher.
Coordination, in other words, was cheaper than inaction.
CEO Times Read
Bessent's operation is a textbook demonstration of what disciplined, strategically self-interested currency diplomacy looks like. Rather than lecturing Tokyo on market purity, the Treasury identified a concrete American interest — stable Treasury demand, a level trade playing field — and acted on it with precision. The notepad photograph, whether leaked by design or not, functioned as a credible commitment device: markets moved before a single dollar was deployed.
Critics of coordinated intervention will argue that governments cannot indefinitely override price signals. That is true. But the degree of US-Japan alignment here, described by analysts as the tightest in decades, raises the cost of speculative yen shorts to a level most hedge funds will not sustain. Capital rewards clear rules. Bessent just wrote one in plain English — on a notepad, in front of a camera.
