Dow Jones Industrial Average traded 143 points, or 0.6%, lower at 21,915, as Apple Inc.(AAPL) shares dropped more than 2% and Goldman Sachs Group Inc.(GS) shares fell 1.7%.
The Nasdaq gave up 13.31 (-0.21 percent) to close at 6,370.46, while the S&P 500 finished at 2,474.92, down 5.99 (-0.24 percent) from its open. The Nasdaq composite fell 35 points, or 0.5 percent, to 6,336.
North Korea claimed "only absolute force" can work on someone as "bereft of reason" as Trump and detailed plans to fire a salvo of missiles into waters around the U.S. Pacific territory of Guam. The precious metal rose 1.3 percent in the previous session, its biggest gain since mid-May, and touched $1,278.66 an ounce, it highest level since June 14.
Pharmaceutical giant Valeant grew 2 percent after news hit the market that the company recorded lower sales in the second quarter, but saw the operating loss significantly lower. Humana rose $3.59, or 1.4 percent, to $253.81.
President Trump's threat of "fire and fury like the world has never seen" on Tuesday elevated concerns, which continued to drag markets lower last night as investors fled to safe havens. The yield on the 10-year Treasury note fell to 2.22 percent from 2.26 percent late Tuesday.
Biotechnology stocks are turning in some of the market's worst performances on the day, resulting in a 2.4 percent drop by the NYSE Arca Biotechnology Index.
The pan-European FTSEurofirst 300 index lost 0.75 per cent and MSCI's gauge of stocks across the globe shed 0.40 per cent.
Analysts said media and entertainment stocks also seemed to get caught up in the broader market drop, but emphasized it was often hard to isolate reasons behind specific stocks' movements. Hong Kong's Hang Seng added 0.6 percent.
The S&P/TSX composite index was down 39.02 points to 15,217.33, with most sectors finishing in the red while bullion stocks surged almost 1.9 per cent. Brent crude, used to price worldwide oils, gained 10 cents to $52.24 in London. Gold settled up 1.4% at $1,256.40 an ounce, then rose almost 2% - to almost $1,283 - after Wednesday's settlement.
Among other markets, oil prices advanced after a US Department of Energy report showed lower oil inventories.
Benchmark U.S. crude fell 22 cents to $49.17 a barrel on the New York Mercantile Exchange.
The Japanese yen strengthened 0.35 per cent versus the greenback at 109.94 per dollar.
Against the Swiss franc EURCHF=EBS, it fared slightly better and was broadly flat on the day at 1.1319 francs per euro.