eyup "Offloading the bonds was the only way for Japan to reduce their losses on the interest rate cut bets." "Japan is under tremendous pressure as the yen has fallen to a 34-year low against the U.S. dollar."

Here's an interesting thread on the matter.

In short: The most important component of US balance of payments by a very large amount as Debt Securities that are 'Long Term'. These were traditionally held by states and are now being picked up by private investors because the current high interest rates make them attractive. So no major issue right now. There's enough willing buyers. These interest rates look to continue too for now, but as soon as interest rates go down these private investors will dump this debt, which states used to hold on to, leading to a potential big problem for the US balance of payments.

It's because people are expecting US to start cutting rates at some point like the other countries have been, and since the rates are currently high it makes the dollar relatively stronger.