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A government would dearly love to deliver, all at once, fast and sustained growth, jobs for everyone who wants one, prices that barely move, and a comfortable external balance — and to do so without trashing the environment or widening the gap between rich and poor. The hard truth at the centre of macroeconomics is that these goals pull against one another. Squeeze inflation out of the system and unemployment tends to rise; stoke demand to cut unemployment and inflation tends to climb; let the economy grow rapidly and the current account deteriorates and carbon emissions mount; redistribute aggressively in the name of equity and you may blunt the incentives that drive efficiency. These are the conflicts and trade-offs between objectives, and the ability to analyse them — to explain why they arise, to draw the diagrams that capture them, and to evaluate how policy navigates them — is the single most heavily examined evaluation skill in the whole macro course. This lesson sets out the four-plus objectives, builds the central analytical device of the Phillips curve (short-run trade-off, expectations-augmented vertical long-run curve, and the rational-expectations critique), works through each major conflict in turn, and then asks the decisive question: can the conflicts be resolved, or only managed? The recurring theme is that supply-side improvement is the one route that can ease several conflicts at once — but it acts slowly, so in the short run the trade-offs bite.
This lesson sits within Section 4.2.3 — Economic performance of the AQA A-Level Economics (7136) specification (the macroeconomics half, 4.2 The national and international economy), and it synthesises the whole of the macro objectives — drawing on growth (Lessons 1–2), unemployment (Lesson 3), inflation (Lessons 4–5) and the balance of payments (Lessons 6–7) — while underpinning the evaluation of macro policy.
Exam Tip: A question that asks you to "evaluate the conflicts a government faces in pursuing its macroeconomic objectives" is really asking for (a) the trade-offs (Phillips curve, growth vs current account, growth vs environment), (b) why they arise, and (c) whether supply-side policy can ease them. Signposting those three moves and ending on the supply-side "holy grail" structures the whole essay.
| Objective | UK Target / Benchmark | Responsible Body |
|---|---|---|
| Sustained economic growth | Steady real GDP growth (trend rate ~1.5–2.5% p.a.) | Government (fiscal policy); Bank of England (monetary policy) |
| Low unemployment | Unemployment at or near the natural rate (~4–5%) | Government (supply-side policy); Bank of England |
| Low and stable inflation | CPI = 2% ± 1 percentage point | Bank of England Monetary Policy Committee (MPC) |
| Satisfactory balance of payments | A sustainable current account (no numerical target) | Government (trade and industrial policy); market forces |
Two further objectives are frequently added: an equitable distribution of income and environmental sustainability (the focus of Lesson 10), and many governments also aim for sound public finances (a sustainable budget deficit and debt). The more objectives a government adopts, the more acute the conflict — a point formalised below by the Tinbergen Rule.
Key Definition: The Phillips curve (A. W. Phillips, 1958) is an empirical relationship showing an inverse correlation between the rate of unemployment and the rate of change of money wages — later adapted to show a trade-off between unemployment and price inflation.
Phillips examined UK data from 1861 to 1957 and found that when unemployment was low, wage inflation was high, and vice versa, suggesting a stable, exploitable trade-off: policymakers could apparently choose a point on the curve, accepting higher inflation in exchange for lower unemployment. The economic logic is the labour market: when unemployment is low, the labour market is tight, firms must bid up wages to attract and retain workers, higher wage costs are passed into prices, and inflation rises. When unemployment is high, excess labour supply weakens workers' bargaining power, wage growth is restrained, and inflation falls. Paul Samuelson and Robert Solow (1960) reinterpreted the relationship for the US as a policy menu linking unemployment to price inflation.
The diagram below is the central picture of this topic: the downward-sloping short-run Phillips curve (SRPC), with the inflation rate on the vertical axis and the unemployment rate on the horizontal axis. A movement down the curve (lower unemployment) comes at the cost of higher inflation, and vice versa.
Exam Tip: Phillips himself found a relationship between unemployment and wage inflation; Samuelson and Solow reinterpreted it as unemployment versus price inflation. Noting this distinction is a precise AO1 point that marks out the strongest answers.
Milton Friedman (1968) and Edmund Phelps (1967), working independently, challenged the idea of a stable, permanent trade-off. They argued that in the short run a trade-off exists, but in the long run the economy returns to the natural rate of unemployment regardless of inflation — so there is no long-run trade-off.
The mechanism rests on adaptive expectations:
The diagram below adds the vertical LRPC and the upward-shifted SRPC₂ to the picture: each attempt to exploit the trade-off ratchets the short-run curve upward, leaving unemployment back at the natural rate U∗ but inflation permanently higher.
Key Definition: The NAIRU (Non-Accelerating Inflation Rate of Unemployment) is the unemployment rate at which inflation is stable. It corresponds to the natural rate and is the point at which the long-run Phillips curve is vertical.
Friedman's policy implication is profound: demand-side policy cannot permanently hold unemployment below the natural rate — any attempt only generates accelerating inflation. The only way to reduce unemployment durably is to lower the natural rate itself, through supply-side policies that improve the functioning of the labour market (better skills, matching, incentives and flexibility).
Robert Lucas (1976) pushed the argument further. If agents form rational expectations — using all available information, not just past inflation — then an announced expansion will be anticipated immediately: workers will demand higher wages at once, and there is no trade-off even in the short run for anticipated policy. Only unexpected policy changes can temporarily move unemployment below the natural rate. This New Classical position implies that systematic, predictable demand management is ineffective at influencing real variables — the policy ineffectiveness proposition.
Exam Tip: In a Phillips curve essay, present the three layers in order: (1) the original curve (a stable, exploitable trade-off), (2) Friedman–Phelps (a short-run trade-off only; the LRPC is vertical at the NAIRU), and (3) Lucas (no trade-off even short-run if policy is anticipated). Then evaluate which view best fits the evidence — the layered structure itself signals AO3/AO4 maturity.
The Phillips curve is the classic expression of this conflict. In the short run, stimulating AD to cut unemployment tends to raise inflation, while contracting AD to cut inflation tends to raise unemployment. UK example: the Bank of England's rate rises from late 2021, designed to bring inflation down from a peak of 11.1%, were expected to raise unemployment — a direct movement up a short-run Phillips curve (lower inflation bought with higher unemployment). The conflict also has a distributional and regional edge that a purely aggregate analysis misses: the unemployment generated by a disinflationary squeeze rarely falls evenly, tending to concentrate on the young, the low-skilled and regions dependent on cyclically sensitive industries, while the benefit of lower inflation accrues broadly (and especially to savers and those on fixed incomes). This uneven incidence is part of why the trade-off is so politically charged, and why "the cost of disinflation" is not just an aggregate output number but a question of who bears it.
Rapid, demand-led growth tends to generate demand-pull inflation once the economy approaches or exceeds its productive capacity (a positive output gap — Lesson 2). However, supply-side-led growth (from higher productivity, new technology or expanded capacity) raises output without inflationary pressure, because it shifts long-run aggregate supply (LRAS) rightward. Achieving growth without inflation is the "holy grail" of macro policy — and the reason supply-side reform is so prized.
The depth of this conflict depends on how much spare capacity the economy has. With a large negative output gap (deep recession), demand-led growth can proceed for some time with little inflation, because firms simply re-employ idle workers and capital. As the output gap closes and the economy nears full capacity, the same demand growth increasingly spills into prices rather than output — the short-run aggregate supply curve steepens. This is why estimating the output gap (Lesson 2) matters so much for navigating the conflict: a policymaker who underestimates how little spare capacity remains will stimulate demand into an inflationary wall, while one who overestimates the gap will tolerate unnecessary unemployment for fear of an inflation that the spare capacity would actually have absorbed.
As the economy grows, rising incomes pull in more imports — especially where the income elasticity of demand for imports is high — worsening the current account (the synoptic link to Lessons 6–7). This growth–external-balance tension is a long-standing challenge for the UK, and it is sharpest where growth is consumption-led: a domestic spending boom draws in imported consumer goods directly. The conflict is softer where growth is export-led or investment-led in tradeable sectors, because such growth tends to strengthen the export side of the current account even as it raises imports of capital goods. Once again the composition of growth, not merely its rate, determines how severe the conflict is — and supply-side measures that raise export competitiveness can ease this conflict at the same time as the growth–inflation one, which is part of why supply-side policy is so prized.
Traditional GDP growth has historically meant rising carbon emissions, resource depletion and pollution — the conflict examined in full in Lesson 10. Whether growth can be decoupled from environmental harm (green growth) is one of the defining debates of the century.
The conflict can run the other way at very low inflation: aiming for zero inflation, or tipping into deflation, can signal weak demand and choke growth (Japan's "lost decades" — Lesson 5). This is precisely why the inflation target is a small positive number (2%) rather than zero.
Pursuing a more equitable distribution of income (through progressive taxation and generous benefits) may blunt the incentives to work, save, invest and take risks that drive efficiency and growth — Arthur Okun's (1975) famous "leaky bucket": redistribution carries an efficiency cost, because some output is "lost through the holes in the bucket" as it is transferred. The counter-argument is that excessive inequality can itself harm growth (by limiting human-capital investment among the poor and weakening demand), so the relationship is not a simple one-way trade-off. This conflict bridges macro and microeconomics and is a rich source of evaluation.
The single most powerful organising insight in this topic is that almost every conflict is a demand-side conflict that supply-side improvement can ease. When the economy is driven by changes in aggregate demand, the objectives genuinely pull against one another: stimulating AD to cut unemployment and raise growth pushes the economy along a given short-run aggregate supply curve and down a given short-run Phillips curve, so prices rise and (as incomes rise and imports are sucked in) the current account deteriorates. The trade-offs are baked into the geometry of moving along fixed curves. This is why pure demand management can only ever relocate the problem — buying lower unemployment with higher inflation, or lower inflation with higher unemployment.
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