Tariffs at Century-High Levels: The IMF's Verdict on the New Trade War

The last time the world saw tariff rates at their current levels, the global economy was in the depths of the Great Depression. The Smoot-Hawley Tariff Act of 1930 raised US import duties sharply, triggering retaliatory measures from trading partners and contributing to a collapse in global trade volumes that deepened and prolonged the crisis. Ninety-five years later, the IMF's April 2025 World Economic Outlook found that effective tariff rates had risen to comparable levels — and issued an unambiguous warning about the consequences.

A tariff is a tax imposed by one government on goods imported from another country. It raises the price of the imported product for domestic buyers, making locally produced alternatives more competitive. The economics are well understood: a tariff redirects production from more efficient foreign producers to less efficient domestic ones, and the economy-wide cost exceeds the protection benefit to any shielded sector. When applied broadly across many product categories, the cumulative drag on trade volumes, investment decisions, and purchasing power becomes substantial.

What the IMF Found in April 2025

The IMF's April 2025 World Economic Outlook identified trade policy uncertainty as one of the two primary drivers behind its downward revision of global growth — alongside tightening financial conditions. The Fund found that effective tariff rates on trade between major economies had risen dramatically, with the United States applying significant new duties across a broad range of imported goods and retaliatory measures being implemented in response.

IMF modelling suggested a sustained tariff escalation could reduce global GDP by up to 1 percentage point relative to the baseline. The Fund also highlighted an inflationary complication: tariffs raise the price of imported goods at precisely the moment central banks are trying to bring inflation toward 2% targets — creating a particularly awkward trade-off for monetary policymakers.

The GDP and Inflation Trade-Off

Tariffs are unusual policy instruments: they are simultaneously inflationary for consumers and deflationary for overall economic activity. When import prices rise, domestic consumers pay more — this is the inflationary channel. At the same time, reduced trade volumes slow economic activity and reduce demand. IMF analysis suggests the inflationary effect is dominating in the short run.

For central banks managing above-target inflation, this is deeply inconvenient. Keeping rates higher controls tariff-driven price increases while the economy is simultaneously slowing — a tightrope several major central banks now walk. The policy dilemma is real: cutting rates too soon risks embedding the tariff inflation impulse; holding too long risks a sharper economic contraction.

Historical Context: Why This Moment Is Significant

For most of the post-war era, the trajectory of global tariffs was consistently downward. The General Agreement on Tariffs and Trade of 1947 and its successor the World Trade Organisation, established in 1995, oversaw successive rounds of multilateral tariff reductions. By the early 2000s, average applied tariff rates across major economies had fallen to single digits.

That consensus has fractured. Political backlash against the distributional consequences of globalisation, strategic competition between major powers, and supply-chain vulnerabilities exposed during the pandemic have all shifted governments toward more interventionist trade stances. The result is a reversal of several decades of liberalisation — compounding to produce tariff levels without modern precedent.

Who Bears the Cost?

The burden of higher tariffs does not fall equally. Small, open economies that depend on exports for a large share of GDP — Vietnam, Malaysia, Mexico, and several sub-Saharan African nations — face disproportionate exposure. Larger domestic markets have more cushion. But even large economies absorb real costs through reduced export competitiveness and higher input prices for manufacturers relying on imported components.

For emerging markets, the impact is compounded. Many lack the fiscal resources to cushion populations against higher import prices. A tariff applied in Washington disrupts not just US consumers — it displaces the export revenues and employment of developing-country suppliers far from where the tariff was imposed. The World Bank estimates that trade disruption disproportionately harms economies where export revenues fund essential public services.

Trade Diversion and Supply Chain Restructuring

One significant economic consequence of high tariffs is trade diversion — the redirection of trade flows away from efficient producers toward tariff-exempt alternatives. When the United States imposes tariffs on Chinese goods, buyers shift sourcing to Vietnam, Mexico, or India — not because those producers are necessarily more efficient, but because they face lower tariff barriers. The global production network becomes less efficient overall, even as bilateral trade between specific country pairs can increase.

This is generating a significant restructuring of global supply chains. Companies are investing in near-shoring — relocating production closer to their main markets — and friend-shoring — prioritising sourcing from politically aligned countries. These are rational responses to tariff risk, but they are expensive: unwinding decades of supply chain optimisation requires substantial capital investment and takes years to complete. During the transition, production costs rise for everyone.

The semiconductor industry illustrates this clearly. Advanced chips had been concentrated in East Asian production hubs because that was economically optimal. Government subsidies and trade restrictions are now creating new capacity in the United States and Europe — at considerably higher cost. The efficiency loss is real and permanent; it simply becomes an accepted cost of supply chain security.

What Comes Next

The IMF and WTO have both called for de-escalation and a return to rules-based trade frameworks. What economics is unambiguous about: sustained high tariffs reduce global efficiency, make production more expensive, reduce the specialisation gains that underpin trade's mutual benefits, and — when retaliatory cycles continue — can contract global trade volumes in ways that harm every economy.

For businesses, the practical response has been to shorten supply chains, near-shore production, and diversify sourcing. In the interim, uncertainty itself suppresses investment. Firms cannot commit to long-term capital expenditure when the rules governing international trade may change quarter to quarter.

The Takeaway

Tariffs are not abstract policy. They raise prices on consumer goods and industrial inputs, slow growth, complicate central bank decision-making, and generate retaliatory spirals that harm everyone involved. The IMF's April 2025 verdict was direct: the current escalation is one of the most significant risks to global economic stability in a generation. The historical record from the 1930s provides a stark reminder of where unchecked tariff escalation can lead — and why the pressure for de-escalation, whatever the political headwinds, remains economically urgent.