Wall Street’s sell-off is kicking back into gear on Thursday, and a U.S. stock market rattled by uncertainty about the economy and President Donald Trump's tariffs is nearly all the way back to where it was on Halloween.

US stock futures slid Tuesday after President Donald Trump made good on his threat to levy hefty tariffs on Canada and Mexico. Dow futures dropped by around 150 points in premarket trading, and futures tied to the S&P 500 and Nasdaq 100 were both around 0.