Having been in finance for these years, there's one thing that left a particularly deep impression on me. I once chatted with a senior forex trader from Japan who had been trading in the foreign exchange market for over twenty years while running a clinic in Shizuoka. He smiled wryly and said, "Without trading forex, I always feel like something is missing. Following the market movements around the world makes me feel more at ease." At that time, I didn't fully understand it, but the more I think about it now, the more I comprehend that feeling.

Last week, there was big news – the Bank of Japan announced an interest rate hike, breaking the zero interest rate situation for the first time in two or three decades. The first thing that came to my mind was the figure of that old gentleman, along with the group of "invisible players" behind him. They are no longer retail investors; calling them the "undercurrent" of global capital flows is an understatement; they are essentially the giant whales capable of stirring the oceans.

**The Invisible "Whale" World**

These people were initially mainly Japanese housewives who were dissatisfied with the low domestic interest rates, so they formed groups to invest abroad. The group has grown larger, and now a large number of middle-aged men have also joined, using an app to operate in the global market. Don't underestimate them – at one point, they accounted for two to three percent of the trading volume in the Tokyo forex market, and they still represent a significant portion of the global retail forex.

Japanese household financial assets total 14 trillion USD, and their strategy is called "yen carry trade": borrowing yen at almost zero interest, converting it into high-yield currencies like USD, and then buying US bonds, US stocks, or even digital assets to steadily earn interest rate differentials. In the past, during Japan's zero interest rate era, this was almost a business of making money while lying down. Even Buffett has done similar things—issuing low-interest bonds in Japan and then turning around to invest.

**The rules suddenly changed**

But this time the Bank of Japan's interest rate hike has directly changed the game. The original arbitrage space has been severely compressed, putting pressure on risk assets like Ethereum and Bitcoin to undergo capital reallocation. As the appreciation of the yen becomes a trend, positions that rely on low-interest arbitrage need to be reassessed. Those once stable income channels have now turned into risk exposures that require cautious handling. This shift in the global liquidity landscape is bound to stir waves in the digital asset market.