A letter from Patrick Billingham of Brighton asks the question that UK industrial policy consistently dodges: if the government is going to put £1.25bn into Rolls-Royce's next-generation narrow-body jet engine programme, why hand it over as a subsidy rather than take an equity stake? The logic is straightforward. A grant transfers public money to private shareholders. An investment would let the public share in the profits, and — as Billingham notes — potentially reduce the tax burden in the long run. The question is not naive. It is the question that separates industrial policy from corporate welfare. Governments routinely take equity in startups (the British Business Bank does exactly this), and sovereign wealth funds worldwide hold stakes in national champions. Norway's Government Pension Fund owns pieces of nearly every major listed company on Earth. The UK, by contrast, defaults to grants, tax credits, and loan guarantees — instruments that socialise risk while privatising returns. Rolls-Royce is not a struggling firm in need of rescue. Its share price has roughly quintupled since its 2022 lows. The company returned to profitability in 2023 and is generating substantial free cash flow. A £1.25bn equity investment at current valuations would give the Treasury a meaningful but non-controlling stake — and a claim on dividends and capital gains that a grant can never deliver. The standard counterargument is speed and simplicity: grants don't require negotiating share prices, don't spook markets, and don't entangle the state in corporate governance. These are real frictions. But they are frictions of convenience, not principle. The state already manages equity positions through UKGI (UK Government Investments) and has done so for decades. The deeper issue is political. Equity stakes make the state a co-owner, which successive UK governments have treated as ideologically unacceptable regardless of the financial arithmetic. The result is a policy architecture that systematically transfers upside to shareholders while loading risk onto the public balance sheet. Billingham's letter, in two sentences, identifies the extraction mechanism that decades of industrial strategy documents have buried in jargon. The remaining letters in the collection — on land measurement in units of Athens, iron-deficiency eye diagnostics, public transport noise fines, and Reform UK's newspaper finding its ultimate use — are classic Guardian readers' correspondence: wry, lateral, and occasionally devastating. The Rothbury estate letter gently skewers the media habit of measuring land in arbitrary capital cities rather than the traditional British unit of Wales. The Reform UK toilet-roll letter needs no editorial comment. But Billingham's letter is the one that deserves policy attention. The UK is entering a phase of significant industrial investment — defence, energy transition, aerospace — and the question of whether taxpayers get grants or equity will determine who captures the value created over the next generation.