Crude oil also was hit hard by the tariff news, with oil prices suffering their worst trading day in 4 years, falling by 8%.
Between the lines: The tariff announcement could not have come at a worse time for the oil market, which was already primed for losses after the Fed's rate cut decision Wednesday. A weak dollar strengthens oil prices, which are measured in dollars.
- The market also is preparing for a major supply surplus in 2020, which is the result of tepid demand growth at a time of surging supply.
By the numbers:
- WTI crude prices fell below $55 a barrel and Brent dipped to $61.
- Energy stocks fell across the board with the SPDR energy exchange traded funds dropping more than 2% on the day as the trade war escalation and fear of higher tariffs stoked worries about slowing demand in China and around the globe.