Akshita Jhalani
Crypto Analyst
I'll be honest, every time the Bank of Japan makes a move, or even hints at one, I watch the crypto market just as closely as I watch the yen. The connection between Japanese monetary policy and Bitcoin has been one of the most underappreciated macro relationships of this entire cycle. And right now, a former Bank of Japan official just issued a warning that makes this worth watching very closely.
Tsutomu Watanabe, an economics professor at the University of Tokyo who previously worked at the BOJ, said the central bank may raise its benchmark interest rate rapidly this year, potentially pushing it above 2%. Japan's current official rate sits at 1%, the result of a series of gradual hikes over the past two years. The 10‑year government bond yield is already sitting above 2.8%, its highest level in at least three decades.
The Yen Is Still Falling Despite Everything
Here's the fundamental problem the BOJ is dealing with right now. Even after raising rates and watching bond yields hit multi‑decade highs, the Japanese yen keeps sliding. It has now fallen to 162.36 per U.S. dollar, a 60% depreciation since early 2021. That's a staggering collapse for one of the world's most actively traded currencies, and it's dropped another 3% just this year.
The theory is that faster, more aggressive rate hikes would finally give the yen enough upward momentum to stop the slide. Whether that works in practice depends on whether global carry trade dynamics, where investors borrow in yen to fund higher‑yielding positions elsewhere, actually unwind at scale.
The Bitcoin Question That Has Two Answers
This is where I find myself genuinely torn, because the conventional carry trade narrative and the actual data are telling different stories right now.
The traditional theory says a BOJ rate hike that strengthens the yen triggers an unwinding of yen‑funded positions across global markets, government bonds, tech stocks, and crypto all get sold as investors repatriate capital to repay cheap yen borrowings. Under that framework, faster BOJ hikes are bearish for Bitcoin.
But here's what the data actually shows. Bitcoin's 52‑week correlation with the USD/JPY exchange rate recently hit 0.90, meaning Bitcoin and the yen have been moving in almost perfect lockstep against the dollar. When the yen weakens, Bitcoin weakens. When the yen strengthens, Bitcoin tends to strengthen too.
That's not a carry trade unwind story. That's a shared macro sensitivity story. If BOJ rate hikes successfully strengthen the yen, and Bitcoin keeps tracking the yen directionally, faster hikes could actually be a tailwind for Bitcoin rather than a headwind.
The Fiscal Problem Nobody Is Saying Out Loud
There's a third angle that several economists have raised but that doesn't get enough mainstream coverage. Japan's government debt level is among the highest in the developed world as a percentage of GDP. Rapid rate hikes dramatically increase the cost of servicing that debt. At some point, aggressive tightening doesn't just affect the yen, it creates genuine fiscal stress for the Japanese government itself.
A Japan fiscal crisis, or even meaningful concern about one, would be an entirely different kind of shock to global markets than a clean carry trade unwind. The implications for Bitcoin in that scenario are considerably more unpredictable.
What I'm Actually Watching
The honest answer is that a BOJ rate acceleration creates genuine uncertainty in both directions for Bitcoin, not clean bearish risk the way most people assume. The positive correlation between BTC and the yen complicates the standard carry trade unwind thesis significantly.
What I'm watching is whether the yen actually strengthens if the BOJ does hike faster, and whether Bitcoin tracks that move higher as the correlation data suggests it should. If that relationship holds, faster BOJ tightening could be the unexpected bullish macro factor nobody in the Bitcoin community is currently positioned for.
That's not a prediction. It's the setup I'm watching most carefully from Tokyo heading into the rest of July.
