Merz’s Collapse Spells Out an Andy Burnham Fiscal Warning

The trajectory of Friedrich Merz carries a direct Andy Burnham fiscal warning: abandoning an election mandate to borrow your way out of a tight spot courts a political and market reckoning, and Britain’s starting position is materially worse than Germany’s was.

Fifteen months into the chancellorship, Merz is trailing the AfD by seven percentage points in the polls, his coalition is fractious, and CDU politicians have begun discussing a Kanzlertausch, or chancellor swap. The AfD is polling above 40% in Saxony-Anhalt ahead of the 6 September state election, which would put it within reach of governing a German state for the first time.

The immediate cause is a broken promise. Merz fought the 2025 federal election on fiscal conservatism. Within days of taking office, he pushed through constitutional changes exempting defence spending above 1% of GDP from Germany’s debt brake (previously capped at 0.35% of GDP in annual net federal borrowing) and created a European Commission-modelled €500 billion infrastructure fund. Germany’s infrastructure genuinely needed it, and the geopolitical case was real. But voters who had endorsed fiscal discipline got the opposite within a fortnight.

Why the Andy Burnham Fiscal Warning Has a Harder Edge for Britain

The comparison for Burnham is instructive, not flattering. He inherits a programme that promised “change” while pledging not to raise the three main taxes on working people, leaving him wanting to spend more with limited room to raise the money. Where Merz at least had a personal electoral mandate to reinterpret, Burnham enters without one: he was not even an MP when Labour won in 2024.

The fiscal arithmetic makes the Andy Burnham fiscal warning sharper still. Germany entered its spending expansion with government debt at 63.5% of GDP, rising to 68%. Britain’s public-sector net debt already stands at 94%, with the Office for Budget Responsibility (OBR) projecting a peak above 96%. Fitch Ratings projects UK general government debt-to-GDP rising from 101% at end-2024 to just above 106% by end-2027, more than double the ‘AA’ median of 49%. The OBR’s own baseline, as reported by The Guardian, shows debt accelerating again from the mid-2030s even under plans intended to stabilise the ratio at around 95% by 2030-31, with the warning that any shortfall in deficit reduction or another economic shock could bring that inflection earlier.

Britain is already running the financing programme that Germany considers extraordinary. The UK plans to issue roughly £252 billion of gilts this year; Germany, with an economy around 50% larger, plans approximately €335 billion of longer-term federal securities. That near-equivalence in volume, despite the size gap, illustrates how stretched Britain’s borrowing base already is.

One partial buffer exists. Fitch notes that the UK’s average debt maturity of 13.7 years provides some insulation against the immediate impact of high nominal gilt yields. But that mitigant does not change the direction of travel, and it does nothing for the risk premium investors may demand if Burnham extends borrowing materially. ONS data show UK public sector net borrowing for the year ending March 2026 was initially estimated at £132.0 billion, which was £19.8 billion less than the prior year and £0.7 billion below the OBR’s £132.7 billion forecast: a marginal beat, not a structural shift.

Defence Equities Offer the Cleaner Investment Angle

For investors navigating the macro noise, defence equities present a more legible setup than gilts. BAE Systems reported a record order backlog of £84 billion for 2025, with the Air segment alone contributing £32.6 billion, according to FlightGlobal. Full-year 2025 operating profit came in at £3.32 billion on sales of £30.66 billion, up 10% year on year, with 2026 guidance pointing to 7-9% higher sales and 9-11% higher operating profit, per Reuters. Rheinmetall’s order book has swollen to around €80 billion. Both reflect a structural shift in European defence spending that predates, and will outlast, whatever the next Budget delivers.

Britain does carry advantages: deeper venture-capital markets, a more flexible labour market, and a floating currency that can absorb external shocks in ways the euro cannot. Depreciation is no free lunch, raising import costs and risking inflation, but the adjustment mechanism exists. Germany has no equivalent.

The question for Burnham is whether those structural advantages are sufficient to give the gilt market confidence if he follows Merz toward a mandate rewrite. Merz had a stronger fiscal starting point, a personal mandate, and still paid a heavy political price. The next Budget on 28 October is the first real test of whether Burnham reads that lesson or repeats it.