A stronger yen is splitting Japan's stockmarket in two

Japan's stockmarket is opening in two directions at the same time. On a recent morning Mitsubishi UFJ Financial Group (MUFG), the country's biggest bank, climbed more than 2% as Toyota Motor, the flagship carmaker, did the same—and a reader who stops at the shared move learns less about a rising market than about a policy tearing it apart. (The same round-up even listed a Chinese drugmaker among the Japanese movers; treat that as the garble of a machine translation, not as data.) The force now deciding which way Tokyo trades is no longer growth. It is the Bank of Japan, and the yen it is letting strengthen.

A subsidy, withdrawn

For nearly three decades a cheap yen was Japan's quiet industrial policy. It kept exports competitive, padded the profits of carmakers and the thousands of suppliers beneath them, and helped push the export-heavy Nikkei to a record above 50,000 by the end of 2025. Its costs landed elsewhere, on households, who paid more for imported food and energy as the currency fell. In July the yen touched 40-year lows near 160 to the dollar. Then the arithmetic changed. An energy shock—the Iran war pushed Brent crude above $100 a barrel—made the cheap-yen arrangement politically untenable, and co-ordinated effort by Tokyo and Washington began pushing the currency back up. The BOJ obliged: in June it raised its policy rate to 1%, the highest since 1995, and its governor has said a hike is on the table at every meeting, including this month's. Traders now price roughly a 97% chance of another quarter-point rise at the meeting next week.

The reversal has been swift and violent. The yen surged about 4.5% in a single week to near 153 in early September, its strongest since February, as the enormous "carry trade"—a record ¥360trn ($2.35trn) of cheap-yen borrowing used to buy higher-yielding assets abroad—began to unwind. Analysts now talk of the currency pushing into the mid-140s if the central bank follows through. For a market built on the subsidy that yen weakness provided, this is not a blip. It is a redistribution.

Banks win, carmakers pay

Watch the two halves of the index and the structure is clear. Higher rates are a gift to Japan's banks. As lending yields rose faster than deposit costs, MUFG's domestic lending spread widened from 0.95% to 1.16%, and the country's three biggest banks earned a combined ¥5.26trn (about $32bn) in the year to March 2026, up roughly a third. The market has noticed: MUFG's shares are up about 48% this year, its recent quarterly earnings have beaten consensus, and AInvest's aggregate signal labels the stock a Buy. In a country where rates stayed near zero for a quarter-century, the mere return of positive margins is a novelty worth paying for.

Toyota is the mirror image. The weak yen was doing the heavy lifting; in August the company built its guidance around an average of ¥160 to the dollar for the year. The yen is already below that and likely heading lower, leaving the forecast stale. Toyota has said the stronger currency will lop roughly ¥110bn off operating profit this year. That lands on top of a stretch already under strain—operating profit fell for a fifth straight quarter in the April-June period, hit by the China slump, Iran-war energy costs and American tariffs—before the currency even turns from friend to foe. In a single August session, when the yen-first fear took hold, Toyota and Honda slid around 4% and some $173bn was wiped off Japanese stocks in a day. That was the market registering the end of an era.

The small print of "Japan"

For a reader outside Tokyo the practical question is what these two opposing trades add up to when bundled. A plain, unhedged Japan exchange-traded fund—the iShares MSCI Japan fund holds about $23bn and has taken in more than $4bn this year from American investors—does not let you choose. It owns both the banks and the carmakers, and it leaves the currency risk unhedged. So American money flowing into "Japan" is, whether its owners mean it to or not, buying both sides of one policy and making a quiet bet that the yen rises—the very bet that now signs the carmakers' earnings lower. The single lines of stock make the choice for you: the bank is a wager on further rate rises, the carmaker a wager that the yen's rise stalls.

The deeper point is distributional. For years the cheap yen transferred wealth from Japanese households to its exporters; interest-rate normalisation and a stronger currency are now reversing that transfer, from corporate profit back towards savers and the cost of daily life. That is why the reversal is not, whatever the exporters' lobby might say, a mistake to be corrected. It is a subsidy coming home. The investor who still wants "Japan" should understand that they are no longer buying a country's revival but choosing a side in its unwinding—and the sharper the Bank of Japan's follow-through, the more one side of that choice thrives at the expense of the other.