Here’s one key thing you should know about Trump’s shock to the world economy: it could work

It’s less than a week since Donald Trump’s sensational announcement that he was unilaterally ending the world’s trading system with the imposition of a 10% minimum tariff for trading with the US – and a very much higher rate for those countries unfortunate enough to have the US as a major export partner. Long-term allies such as Japan and South Korea have been hammered with tariffs of around 25%, while export-dependent poorer countries such as Vietnam, which sells about a third of its exports to the US, have been hit with tariffs in excess of 45%. A further round of global debt crises is possible as heavily indebted countries face the sudden loss of export earnings.

Global stock markets have tumbled as panicked investors dump shares, and political condemnation has been near-universal. China has already retaliated with 34% tariffs, threatening an escalating trade war. Right now, it looks and feels like disastrous overreach by a uniquely erratic administration at the behest of a president with a terrifyingly limited grasp of how the modern economy works.