The RBA Hiked to an 18-Year High and the Australian Dollar Fell - That Is the Fed's December Problem

The Reserve Bank of Australia (RBA) lifted the cash rate target 25 basis points to 4.85% on November 3, 2026, its fifth increase of 2026 and its highest rate since November 2008. Six of the nine members voted for the hike; three wanted to leave the target unchanged at 4.60%. The same statement pushed the inflation path out: inflation is now expected to stay above 3% for the coming year, and is not expected to reach the top of the 2% to 3% target band until late 2027 - about three quarters later than the board had previously forecast. The tightening and the forecast revision ran in the same direction, which is the opposite of what a credible disinflation looks like.

The market had already paid for this hike. ASX cash rate futures priced roughly 78% odds of a 25 basis point move the day before the announcement, and one major bank's economists put the market near 90%. What was not priced was the reaction: the Australian dollar fell to 0.6982 on November 3, having traded as high as 0.7057 only a few sessions earlier, even as the cash rate reached an 18-year high and Brent traded above $104. A currency that will not rally on a hawkish hike is pricing the cost of the hike, not the confidence behind it.

Australia's consumer price index rose 4.3% in the 12 months to September 2026, up from 4.0% a month earlier, with the monthly index up 0.8% and the September quarter up 1.3%. Trimmed mean inflation - the measure the RBA steers by - was 3.6%, and the quarterly trimmed mean rose 1.0%. The composition is the story: automotive fuel prices rose 9.4% in September alone, transport was up 8.7% year on year, and housing added 5.2%. Fuel is the accelerant rather than the whole story, because trimmed mean inflation of 3.6% already sits about a point above the RBA's 2.5% midpoint.

Australia's own budget papers assume the shock fades. The Treasurer's central forecast had oil around $100 a barrel until the end of next month, gliding to $80 by the end of June 2027, with inflation peaking near 5%. Brent is at $104.70 today and the RBA now sees inflation above 3% for a full year. The fiscal and monetary forecasts have quietly parted company, and the gap between them is one oil price.

The fiscal and monetary authorities are pulling in opposite directions, and the documents show it. The 2026-27 Budget, delivered on May 12, 2026, more than halved the fuel excise, zeroed the heavy vehicle road user charge and put $14.8 billion into fuel resilience and supply chain security - measures that land directly on the transport component of CPI that is now running at 8.7%. The same budget handed every working Australian a new tax offset worth up to $2,816 in 2028, while the deficit for the coming financial year was still $31.5 billion on gross debt of $982 billion. The RBA is therefore the only institution actually doing the tightening.

The Federal Reserve has been tightening again, but it started later and is moving slower. It hiked on September 16, 2026 - its first increase since 2023 - to a 3.75% to 4.00% target range, then held on October 28 by ten votes to two, with Governor Lisa Cook and Governor Beth Hammack dissenting in favour of a 25 basis point increase. Futures were pricing roughly an 80% chance of a hike at the December 8-9 meeting. The contrast with Canberra is the point: the RBA's dissenters wanted to hold while the Fed's dissenters wanted to hike, yet the RBA's cash rate now stands 85 basis points above the top of the Fed's range.

Kevin Warsh's framing - that inflation can return to 2% without throwing sand in the gears - is a supply-side argument, and it is why the September projections put the policy rate at 4.00% to 4.25% by the end of 2026 and 2027. The credibility test is whether a December hike reads as the last one. The RBA's own decision is doing the market's work for it: an 18-year-high rate with inflation forecast higher says the shock is not temporary, so a first Fed hike cannot plausibly be the last.

Term premium is the price of all this, and it has already moved. The Federal Reserve's own ACM model put the ten-year term premium at 0.9595% on September 18 and in a 0.94% to 1.00% band through the second half of October. The ten-year Treasury yield was 4.94% on October 30 and 4.91% on November 2, against a 2026 range of 3.97% in late February to 5.31% in early October. Washington's arithmetic has changed with it: gross federal debt above $40 trillion, publicly held debt at 100% of GDP, and fiscal 2026 net interest costs above $1 trillion - more than defence spending. A central bank that hikes while the government's interest bill doubles forces the long end to absorb both shocks.

This is why the Fed's chair is now described as managing the curve, not only the policy rate. Robin Brooks argues that the Fed's yield-curve management reflects concern about the precarious U.S. debt picture rather than the hot inflation prints, and the reported response has included Treasury Secretary Scott Bessent announcing buybacks of more long-term bonds and currency-market intervention to prop up the yen so Japan does not dump its U.S. holdings. The CBO arithmetic explains the urgency: 150 basis points above its 4.3% baseline would add $4.9 trillion to net interest costs over a decade and take publicly held debt to 133% of GDP by 2036. Long duration has stopped being a hedge against the policy that creates it.

The carry trade is built on cheap yen funding. The Bank of Japan held its policy rate at 1.25% on October 30 in an 8-1 vote, with one member voting for 1.5%, and the bank has signalled further increases. The yen sits at 157.87 per dollar after touching 158.28 on October 28, so the funding side of the trade is still generous and the crowding is the vulnerability. Korea is tightening too: the Bank of Korea held at 3.00% on October 22 after two back-to-back hikes, with consensus putting the peak at 3.50% and one more hike priced for November. Three central banks now have to hike or validate the oil shock, and the yen is the currency that pays for all of it.

Follow the money through the chain. Upstream, the oil price is doing the work and recirculates the oil windfall into the very assets the central banks have to defend: ExxonMobil's third-quarter earnings of $15.4 billion, more than double the $7.5 billion of a year earlier, came with $25.65 billion of operating cash flow. Downstream, the cost of that windfall arrives as a discount rate: JPMorgan Chase earned $27.04 billion of net interest income in the third quarter, about 13% more than a year earlier, with the Fed's higher funds rate in place for only a fortnight of that quarter. In Hong Kong, HSBC's banking segment made $2.57 billion before tax.

Over one to three years the structural test is whether an oil-driven inflation wave can be beaten without a recession, and the RBA's own forecast concedes the timing: inflation stays above 3% for a year and is not expected back at the top of the target band until late 2027. Australia is a commodity economy whose currency refused to rally at a 4.85% cash rate, so the RBA is taxing demand in a country that is not receiving a terms-of-trade offset. That is the difference between a hiking cycle that ends and one that becomes a fiscal adjustment. Rates this high, in an economy whose currency won't rally, are a demand tax rather than a victory lap.

The Reserve Bank of Australia did something Washington has not: it raised rates five times in 2026 to an 18-year high while raising its own inflation forecast, with a three-member dovish minority and a currency that fell on the news. That is what a central bank looks like when the shock is imported, fiscal policy is unhelpful and the currency is not cooperating. Makes the December Fed hike the most crowded and least informative trade of the quarter: at roughly 80% priced, a hike confirms what is already known, and a pause contradicts the central bank that has gone furthest.