At the start of 2018, after the first full year of the Donald Trump presidency, it was still just about possible to believe the US leader’s belligerence on trade policy was just for show. Frothing rhetoric had resulted in several investigations launched and a lot of threat about direct action but nothing concrete.

Twelve months later, the idea that Mr Trump’s protectionism was purely rhetorical has been disproved comprehensively. Tariffs on steel and aluminium have been applied to trading partners around the world, ostensibly on national security grounds but including traditional foreign policy allies as well as foes. Canada and Mexico were forced into a renegotiation of the North American Free Trade Agreement (Nafta), which became the US-Mexico-Canada Agreement (USMCA) — a clumsier arrangement, both in name and substance. Threats of car tariffs against the EU forced Brussels reluctantly to the negotiating table. And most dramatically of all, Mr Trump imposed waves of tariffs against China covering around half of the country’s exports to the US.

Meanwhile, the US weakened the pillars of the trading system that supposedly constrain it from acting in such a unilateral way, continuing to deprive the World Trade Organization’s dispute-settlement process of judges and hence further eroding even its theoretical ability to hold Washington to WTO rules.