Global leaders had some difficult talks at the recent G20 summit in Buenos Aires. But there was clear consensus on at least one topic: the need to prepare for the risks to economic growth, whether from tightening financial conditions or trade and political tensions, which are clearly gathering.

Ten years ago, central banks played a huge role in lifting countries out of what could have been a recession as severe as the one in the 1930s. A co-ordinated fiscal stimulus was orchestrated and took place for a couple of years, but then was halted in some countries, not least in Europe, where the sovereign debt crisis hit the eurozone some years after the global financial crisis.

Today, growth in gross domestic product has recovered but not to pre-crisis levels, productivity has waned and many policymakers fear they no longer have the ammunition to help much in the event of a marked slowdown. Monetary policy rates remain low, sometimes even at zero. In a number of countries, the build-up of public debt leaves little space for individual governments to raise spending in a marked downturn.