Three central banks, three diverging paths — and a rupee that is watching all of them

Japan's rate rise to a 31-year high is best understood through the lens of the carry trade, a strategy in which investors borrow in a low-interest-rate currency — in this case the yen — and invest the proceeds in higher-yielding assets abroad. For most of the past three decades, the Bank of Japan kept rates near or below zero, making the yen the world's preferred funding currency for this trade. When the BoJ raises rates, the cost of borrowing in yen rises, the expected return on the trade falls, and investors begin to close their positions: they sell the foreign assets, buy back yen, and the yen appreciates. That appreciation then feeds back into further position-closing, because a stronger yen makes the yen-denominated debt more expensive to repay.

The mechanism matters for India specifically because a portion of the foreign institutional investment in Indian equities and government bonds is funded, directly or indirectly, through yen carry. A disorderly unwind — the kind seen briefly in August 2024, when a smaller BoJ surprise triggered a global equity sell-off — would put downward pressure on the rupee and upward pressure on Indian sovereign yields at precisely the moment the RBI is already navigating the Fed's own tightening cycle. The rupee's recovery to 95.73 today suggests the unwind is so far orderly, but the honest evaluation is that one session's data is thin evidence: the 1998 and 2013 episodes both showed that carry-trade reversals can accelerate non-linearly once a threshold of position-closing is crossed. Whether today's BoJ move proves a managed transition or a trigger depends on the pace of further hikes — and the BoJ has not yet signalled that pace.

The Bank of England's decision is a live illustration of the sacrifice ratio — the concept, developed in the monetary economics literature associated with Arthur Okun and later Ball, that measures how much output and employment must be lost to reduce inflation by one percentage point. The MPC appears to have concluded that the sacrifice ratio in the current UK context is too high: raising rates now, when growth is already fragile and energy costs are supply-driven rather than demand-driven, would destroy output without reliably reducing the inflation that originates abroad in oil markets.

The counter-argument — and it is a strong one — is that holding rates when inflation is at 3.1% and rising risks de-anchoring inflation expectations, the process by which households and firms stop believing the central bank will hit its 2% target and begin pricing that disbelief into wage demands and contracts. Once expectations de-anchor, the sacrifice ratio rises further, because the Bank must then do more tightening later to restore credibility. The 1970s UK experience is the canonical precedent: the Bank of England held rates too long as oil-driven inflation took hold, expectations shifted, and the eventual correction under Thatcher in 1979–80 required a severe recession. The more convincing reading is that the MPC is betting the current inflation is transitory enough that the credibility cost of holding is lower than the output cost of hiking — a bet that is reasonable but not risk-free, and one that the next two months of wage data will either vindicate or refute.

Saudi Arabia's rerouting decision is best analysed as a supply-side intervention in a market where price had been elevated by a risk premium — the extra amount buyers pay above the fundamental cost of production to insure against the possibility of a supply disruption. Risk premia are not driven by actual shortfalls in supply; they are driven by the probability that a shortfall will occur. When Saudi Arabia demonstrates that it can move oil around the Strait of Hormuz, it reduces that probability, and the premium falls even if not a single barrel of supply has actually been lost.

For an IB Economics student, this is a useful case for distinguishing between a shift in the supply curve and a shift in the demand curve for oil. The West Asia crisis did not shift the supply curve leftward — production had not yet fallen — but it shifted the demand curve for oil futures rightward, as buyers paid more to secure forward contracts against the risk of future scarcity. Saudi rerouting shifts that demand curve back toward its pre-crisis position. The distinction matters because the policy response differs: a genuine supply shortfall requires either increased production or demand destruction, whereas a risk-premium spike can be deflated by credible signals of supply resilience. Whether today's price slide is durable therefore depends not on Saudi production capacity — which is not in doubt — but on whether markets believe the rerouting is sustainable at scale for as long as the conflict persists.

The proposal for Canadian 'associate membership' in the EU is a case study in what political scientists call institutional balancing — the strategy by which states use multilateral institutions and alliances to constrain or offset the power of a dominant actor, rather than confronting that actor directly. Canada, facing sustained US tariff pressure under the active thread of the US–Canada trade war, cannot match American economic weight bilaterally. By deepening its institutional ties with the EU, Ottawa effectively enlarges the coalition it can call upon and raises the cost to Washington of further economic coercion: any US tariff on Canada now risks a coordinated EU–Canada response.

The honest evaluation, however, is that 'associate membership' is currently more political signal than legal reality. The EU's existing associate arrangements — with countries such as Ukraine and Moldova — are accession-track relationships governed by specific treaty provisions that do not map onto Canada's situation. Creating a new category would require unanimous agreement among all 27 member states, ratification in national parliaments, and potentially referenda in some countries. The precedent of CETA, which took seven years to negotiate and was nearly derailed by the Belgian region of Wallonia in 2016, illustrates how difficult EU treaty-making is in practice. The more convincing reading is therefore that the political signal — Canada is reorienting westward across the Atlantic — is real and consequential, while the legal architecture to give it substance remains years away. Whether the signal alone is enough to deter further US economic pressure is the question the next phase of the US–Canada trade thread will answer.