The behaviour of equity markets over the course of this extraordinary year has come close to matching the dictionary definition of levitation. The Trump trade war, spiralling fiscal deficits and public debt, pervasive geopolitical risk, the radical dismantling of the postwar international order, declining global growth prospects — all have failed to hold back the magical rebound after investors’ initial panic in April over Donald Trump’s erratic on-off tariff tantrum.

Applying the yardstick that investment sage Warren Buffett regards as the best single measure of market valuation — stock market capitalisation relative to GDP — US equities are at historic record levels. The UK market has lagged behind the US on the GDP-ratio but the FTSE 100 index has nonetheless ventured into record high territory, while other developed world markets have proved surprisingly resilient.

In the face of another Trump tariff deadline on August 1, battle-hardened markets seem more vulnerable to a modest fit of the vapours than abject capitulation in response to this new test of nerves.