Nicholas Spiro, a partner at Lauressa Advisory, a specialist London-based real estate and macroeconomic advisory firm, writes:

Last week’s breakdown in negotiations between the North American neighbours, which triggered the imposition of US tariffs of 50 per cent on a wide range of Canadian goods, showed the degree to which Trump’s trade policies are vindictive, politicised and self-defeating.

According to Canada’s Prime Minister Mark Carney, who has responded in kind by announcing levies of up to 50 per cent on hundreds of US goods, the White House changed the terms of the deal at the eleventh hour.

Self-harm has been the main consequence of Trump’s protectionist and highly expansionary fiscal policies. While the entire world is contending with the geopolitical and economic fallout from Trump’s second presidency, the biggest casualty – and the one that matters most to global markets – is the management of the US economy.