TOKYO - Prime Minister Sanae Takaichi’s government faced a sharper market test on September 9 as the yen’s rapid rebound began pressuring global carry trades, turning expectations of a Bank of Japan rate hike into a political challenge for an administration still trying to balance household relief, fiscal discipline and economic security.
The yen has strengthened sharply as investors prepare for the possibility that the BOJ will raise its policy rate at its September 17-18 meeting. The move has started to unwind part of the yen carry trade, a long-running strategy in which investors borrow yen at low interest rates and invest the money in higher-yielding currencies and assets.
That trade expanded over many years because Japan remained a low-rate economy while the United States and other major economies offered much higher returns. But the logic of the trade weakens when the yen rises and Japanese rates are expected to climb. Reuters reported that cross-border yen borrowing reached an estimated 360 trillion yen in March, showing the scale of exposure that could be affected if the carry trade keeps reversing.
For Takaichi, the market shift is politically complicated. A stronger yen helps ease import-driven inflation by lowering the cost of food, fuel and raw materials, and it gives the government a stronger answer to criticism that the weak currency has damaged household purchasing power. But a rapid yen rebound also reflects rising expectations of higher Japanese interest rates, which could make government borrowing, business investment and mortgage costs more expensive.
That puts the BOJ at the center of the next political test. Markets are increasingly pricing in a 25-basis-point rate hike to 1.25% next week, after the central bank raised rates to 1% in June and held steady in July. The question is no longer simply whether the BOJ will act, but whether Takaichi can absorb the consequences of a more hawkish central bank without weakening her own economic agenda.
Takaichi has promoted a 370 trillion yen public-private investment roadmap through fiscal 2040, covering strategic areas including artificial intelligence, semiconductors, shipbuilding, energy, space, quantum technology and advanced manufacturing. Her government is also pursuing defense expansion and a temporary cut in the consumption tax on food from 8% to 1% from April 2027.
Those policies require credibility in both directions. Voters want relief from high prices and a stronger economy. Markets want proof that the government can fund its promises without relying on the BOJ to suppress interest rates or absorb fiscal pressure.
Rising Japanese bond yields are now testing that credibility. Fitch Ratings said on September 9 that higher Japanese government bond yields may encourage domestic institutional investors to keep more money at home. The agency expects BOJ policy rates to rise more quickly than markets currently anticipate in 2026 and 2027, reflecting stronger inflation, better growth and fiscal concerns.
That would represent a major shift in Japan’s financial structure. For years, low domestic yields pushed Japanese capital overseas in search of returns. If domestic yields become more attractive, banks, life insurers and pension funds may have more reason to invest at home. That could support the yen and reduce some overseas capital outflows, but it could also reduce Japan’s role as a source of cheap global funding.
Politically, Takaichi could present that shift as a sign of restored confidence in Japan. A stronger yen, higher domestic returns and more capital staying at home fit her argument that Japan must rebuild national strength through growth and strategic investment. But there is a danger that the same shift becomes a warning about fiscal costs. If yields rise too quickly, government debt-servicing costs will climb, placing more pressure on the budget.
That is why the food-tax cut remains such a sensitive issue. The government wants to reduce the food consumption tax from 8% to 1% for two years from April 2027, while also providing payments to effectively cover the remaining 1%. The measure is intended to give households visible relief from food inflation, but it is expected to create a large revenue shortfall.
Takaichi has said the government will not rely on special deficit-covering bonds, instead pointing to budget reforms, non-tax revenue and reviews of recent price-relief spending. But markets will judge whether those explanations are sufficient. If bond yields continue to rise, investors may demand a more detailed funding plan before the autumn Diet session.
The yen’s rise also changes the political narrative around currency policy. In July and August, the main concern was that the yen was too weak, raising import costs and forcing rare U.S.-Japan intervention. Now the issue is whether a stronger yen and higher yields could tighten financial conditions too quickly.
U.S. Treasury Secretary Scott Bessent has become an unusually visible figure in that debate. He warned currency traders not to bet against the yen after the earlier joint U.S.-Japan intervention, suggesting that Washington is prepared to use financial power more aggressively as part of its foreign policy. His comments reinforced the impression that the United States wants Japan to maintain a credible policy mix, including BOJ action if needed to stabilize the currency.
That U.S. role gives Takaichi support but also limits her room for maneuver. American backing helped Japan counter speculative yen weakness, but it also increases pressure on Tokyo to accept higher rates and stronger currency discipline. If the BOJ hikes next week, it will be seen partly as a domestic inflation decision and partly as a sign that Japan is aligned with U.S. expectations on yen stability.
For the BOJ, the challenge is to avoid looking either politically captured or externally pressured. Governor Kazuo Ueda must explain any rate decision as based on inflation, wages, growth and financial stability, not as a response to the Takaichi administration, the U.S. Treasury or short-term currency moves.
The stakes are high because the carry trade can affect global markets. A rapid unwind of yen-funded positions can force investors to sell higher-yielding assets and repurchase yen, creating volatility beyond Japan. So far, Reuters reported that markets have remained relatively calm, but the scale of yen borrowing means next week’s BOJ decision could still have wider consequences.
China added another layer to Takaichi’s political challenge. Japan has protested Beijing’s new measures against Japanese exports of dichlorosilane, a key semiconductor production material. Chinese importers must pay cash deposits of up to 99.2% on purchases of the material while Beijing investigates alleged anti-dumping violations.
The measure directly touches one of Takaichi’s strategic priorities. Japan is a major supplier of high-purity materials used in semiconductor production, and the government has placed chips at the center of its economic-security and industrial-revival agenda. China’s move therefore gives Takaichi a concrete example of why Japan needs stronger supply-chain resilience.
But it also shows the economic cost of worsening relations with Beijing. China’s action follows months of tension after Takaichi’s remarks that a Taiwan contingency could amount to a survival-threatening situation for Japan. If China continues using trade measures against Japanese companies, economic security could become not only a policy theme but a source of business uncertainty.
That creates a difficult political balance. Takaichi can argue that Japan must reduce dependence on China and protect strategic industries. Business groups may agree in principle, but they will also want the government to manage tensions carefully so that export restrictions, retaliation and supply disruptions do not hurt Japanese firms.
The September 9 political picture is therefore defined by three linked pressures: the yen, the BOJ and China. A stronger yen helps households but raises the cost of Takaichi’s fiscal agenda. Higher yields may bring domestic capital home but also increase debt-service pressure. China’s chip-material measures strengthen the case for economic security but create new risk for Japanese exporters.
The central question is whether Takaichi can turn market and diplomatic pressure into a coherent governing story. If the BOJ raises rates next week without triggering bond-market stress, if the yen remains stable, and if the government can explain the funding for food-tax relief, Takaichi may be able to argue that Japan is regaining policy credibility. If higher rates hurt growth, yields rise further, or China’s trade measures escalate, the administration could face a difficult autumn in which its main policies begin to collide.
What To Watch Next
The BOJ’s September 17-18 meeting is the immediate focus. Markets will watch whether the central bank raises rates to 1.25% and how Governor Kazuo Ueda describes the path for further increases.
The yen carry trade remains a major market risk. A faster unwind could create global volatility and increase political pressure on both the BOJ and the Finance Ministry.
Japanese government bond yields should be watched closely. Higher domestic yields may support the yen and keep capital at home, but they also raise the fiscal cost of Takaichi’s agenda.
The government still needs to explain how it will fund the planned food-tax cut without special deficit-covering bonds, especially before the autumn Diet session.
Bessent’s currency comments suggest Washington will remain closely involved in yen policy, increasing pressure on Japan to maintain a credible monetary and fiscal stance.
China’s measures against Japanese chip-material exports could keep economic security at the center of political debate and may force the government to offer support to affected companies.
Opposition parties are likely to frame the yen and bond-market shifts as evidence that Takaichi’s fiscal and monetary strategy is being corrected by markets rather than controlled by the government.
