When the US and Japan teamed up to buy yen in early August, the financial world braced for impact. The last time these two coordinated a currency intervention was 1998, back when the Asian financial crisis was redrawing the map of global finance.

The Bloomberg EM FX Carry Risk Premia Index dropped roughly 1% in the aftermath. For context, the August 2024 yen rally triggered a 4% decline in the same index.

What actually happened

The coordinated intervention landed on or around August 1, with official confirmation from the US Treasury and Japan’s Finance Ministry arriving on August 3-4. US Treasury Secretary Scott Bessent and Japan’s Finance Minister Satsuki Katayama framed the move as necessary to maintain global stability amid rising exchange rate volatility.

President Trump also weighed in publicly, positioning the intervention as a critical stabilization effort.