The curve's power lies in what it makes visible that aggregate statistics conceal. GDP per capita rose across the period in almost every region. Global poverty fell substantially. Average incomes improved. By any measure of the aggregate, globalization was a success. The curve showed that the aggregate was the sum of three distinct distributional experiences — the rising Asian middle, the stagnating Western middle, and the soaring global elite — and that averaging them into a single number erased the specific populations whose trajectories diverged.
The valley of the curve — the stagnation of developed-world lower-middle and middle classes — became the political story of the 2010s. Populist movements, Brexit, the realignment of working-class voters toward anti-establishment parties, the collapse of the centrist consensus across Western democracies: these were the political consequences of a distributional outcome that the aggregate statistics had denied for two decades. The curve did not cause the backlash; it named it. Once named, it could no longer be dismissed as perception.
Milanovic has been careful to note that the shape of the curve was not a function of globalization-the-process but of globalization-within-specific-institutional-contexts. In Nordic economies with strong labor institutions and redistributive taxation, the valley was shallower. In Anglo-American economies with weaker institutions, it was deeper. The technology was held constant; the institutions varied; and the institutions determined the distributional outcome. This is the lesson that the AI elephant forces back onto the discourse.
The AI elephant is forming faster than its predecessor — in months and quarters rather than decades — and the analytical challenge is to draw it prospectively rather than retrospectively. The structural logic is clear: concentrated capital ownership at the trunk, AI-complementary knowledge workers on an upper hump, a valley of compressed professional middle classes, and excluded populations at the left tail falling further behind through differential acceleration.
Milanovic and Christoph Lakner developed the curve through the painstaking reconciliation of household income surveys across more than a hundred countries, using purchasing power parity adjustments to make incomes comparable across radically different price levels. The methodological infrastructure required two decades of work at the World Bank's research department, building a global household database that had not previously existed. The chart that emerged in their 2013 paper was the first picture of global income distribution drawn from consistent microdata rather than from aggregated national statistics.
The name came later, attached by readers who recognized the shape before they had a technical vocabulary for what it showed. The recognition was the point: the curve worked because its shape made the distribution legible to populations who could not parse Gini coefficients or Theil indices but could see an elephant.
Aggregate conceals distribution. The same technological transition that raised global GDP per capita produced three dramatically different experiential regions. Averaging them erases the specific populations whose trajectories diverged, generating a statistical picture that bears no resemblance to lived experience in any particular place.
The valley is political. The stagnation of developed-world middle classes produced the populist realignments of the 2010s. Distributional experience, not aggregate performance, determines political trajectories — a lesson the AI discourse has not yet absorbed.
Institutions, not technology, determine shape. The same globalization process produced shallower valleys in Nordic economies and deeper ones in Anglo-American economies. The institutional variables — taxation, labor protections, social insurance — set the gradient.
Visibility changes politics. The chart's power was making distribution impossible to ignore. Any political economy of AI's distribution requires an equivalent act of visibility before the default trajectory hardens.
Retrospective is too late. The globalization elephant was drawn after two decades of distributional damage. The AI elephant must be drawn prospectively, from structural analysis, with enough clarity to motivate institutional action before the populations in the valley have fully felt their condition.
Critics have challenged the curve's interpretation: some argue that the valley reflects Eastern European collapse rather than Western stagnation, that the time window is idiosyncratically chosen, or that dollar-denominated comparisons obscure real welfare improvements. Milanovic has engaged these critiques with updated data that largely preserves the original shape. The more fundamental debate is interpretive: techno-optimists argue that subsequent data shows global convergence continuing; Milanovic's framework responds that the within-country divergence — particularly the rise of the homoploutic elite — has accelerated even as between-country convergence continues.