Hedge fund manager Ray David found himself scrambling to redo his entire pitch book just before he was due to fly out to Perth for a series of client meetings after an escalation in the US trade war had wiped trillions of dollars from Wall Street in a single session.

David watched on as investors dumped US stocks, sending the S&P 500 plunging 6 per cent after Beijing hit back at US President Donald Trump’s punitive tariffs with an extra 34 per cent levy on US goods. (China has since bumped up its overall tax on US goods to 125 per cent.)