Reciprocal tariffs may be a triple threat, at least according to the US president. They could incentivise foreign producers (or US companies working abroad) to build facilities stateside and hire American workers, pressure trading partners to lower their own barriers, and – perhaps unofficially – generate revenue to help pay for tax cuts.

The exact details are still being finalised, but in essence, new import taxes will be tailored to each of America’s trading partners. As well as matching other countries’ tariffs on US goods, they’ll be designed to counter other practices seen as disadvantaging American manufacturers – including unfair subsidies, strict regulations, value-added taxes (VATs), managed exchange rates, and weak intellectual property protections.

Problem is, these so-called “non-tariff barriers” are hard to quantify. That’s creating an enormous challenge for the Office of the US Trade Representative and the Commerce Department, tasked with proposing bespoke levies for each country. If history’s any guide, the president will likely announce rough measures first, then negotiate and refine the details later.

Emerging markets would be hit the hardest by the US matching existing tariffs. India, Argentina, and much of Africa and Southeast Asia would be most exposed, according to Bloomberg Economics. However, it’s clear that non-tariff measures are designed to target the eurozone – with its strict regulations and VAT – and China – with its heavy subsidies to domestic industries and weak intellectual property protections.

All the uncertainty has shaken financial markets, prompted economists to cut their US growth forecasts, and forced the Federal Reserve to consider the potential inflationary impact of higher import costs. The real test of the president’s strategy will be whether escalating tariffs reshape global trade in America’s favor – or spark a backlash that does more harm than good.