Bessent presses financial power abroad while the bond rout deepens at home

Treasury Secretary Scott Bessent said a large bank will be sanctioned on Monday as part of the administration’s Iran strategy¹. The scope of secondary sanctions was also expanded to cover those doing business with Iran in industries including shipping and technology¹.

Bessent has publicly backed using American financial power as a foreign policy tool, citing Argentina as the front-runner for that approach and saying it was his belief that the Milei government had sound policies².

At home, the Treasury moved to buy back up to three times its usual amount of long-term debt as the administration continued trying to bring borrowing costs down⁵. The effect did not last: by reducing supply the buybacks temporarily pulled down yields, but the move was short-lived⁷. Asked about criticism of the programme, Bessent said he was not sure what the beef is⁷.

Why it matters to investors

The bond market is the immediate scoreboard. As the rout deepens, pressure is growing on Bessent to restore calm⁶, and the buyback has not yet delivered it⁷. A Treasury that cannot damp long-end yields with its own balance sheet has fewer tools left than the announcement implied.

The currency leg carries its own risk. Bankers warn that Bessent’s exceptional interference in Japan’s monetary affairs risks damaging the Bank of Japan’s credibility³. His warning that he is the house now spurred yen buybacks by short-sellers, amid speculation that the Bank of Japan will accelerate the pace of its rate increases⁴.

That is an unusual position for a US Treasury Secretary: influencing another central bank’s path while relying on foreign demand to absorb domestic issuance. The sanctions programme adds a third front, since secondary sanctions on shipping and technology reach counterparties well beyond Iran itself¹.

What to watch

The first event is the sanctioning of the unnamed large bank, and whether the designation lands on an institution large enough to move credit or trade finance¹.

The second is the next buyback operation. If a tripled purchase produced only a short-lived decline in yields^5,7, the market’s verdict on supply management is already in, and the pressure on Bessent to find another instrument grows⁶.

The third is Tokyo’s response. If the Bank of Japan accelerates its rate increases in the wake of the intervention⁴, the credibility concern raised by bankers becomes a policy fact rather than a warning³, with consequences for the cross-border flows that fund the American deficit.