US stock sell-off worsens as traders ask how much economic pain Trump will allow

The options floor at the New York Stock Exchange in New York (Seth Wenig/AP)

The US stock market’s sell-off is worsening on Monday as Wall Street questions how much pain President Donald Trump is willing for the economy to endure in order to get what he wants.

The S&P 500 was down as much as 3% in afternoon trading, coming off its worst week since September.