Treasury Intervention Strengthens Yen, But U.S. Borrowing Costs Continue to Climb

The U.S. Treasury's intervention in the yen has had a positive effect on Japan's currency, causing it to strengthen by about 6% since late July. This move was made in coordination with Japan and saw the U.S. Treasury sell euros to buy yen, a rare instance of bilateral currency intervention.

The operation, valued at $500 million, has been effective in stabilizing the yen despite some analysts questioning its durability without higher Japanese interest rates. Other factors supporting the currency include firmer expectations for rate increases and stronger domestic demand for government bonds.

Treasury Secretary Scott Bessent defended the move, which has come under criticism from Senator Elizabeth Warren. He also signaled that he believes he has a better understanding of the Bank of Japan's next steps than the markets do.

However, the strengthening yen does not address the larger issue of rising U.S. borrowing costs, which have been driven up by inflation and fiscal concerns. The 10-year Treasury yield rose above 4.95% this week, its highest level in three years, while the 30-year yield surpassed 5.3%, a multi-year high.