The Dow Jones industrial average lost 204 points, or 0.9 percent, to 21,844.
The influential financial stocks were among the biggest drags on the index, with Royal Bank of Canada down 1.0 percent to C$93.36, and Manulife Financial Corp falling 2.8 percent to C$24.93.
The Nasdaq composite lost 18.13 points, or 0.3 percent, to 6,352.33.
All three major equity benchmarks stumbled firmly lower on Thursday, with the trifecta of indexes on track to fall in three consecutive sessions in unison for the first time since mid April amid a persistent war of words between the USA and North Korea.
Syrian army closes in on IS-held town in Raqqa
The Syrian government has said the United States forces were committing "crimes" by killing civilians on a daily basis. She said however that the 2017 returns were less than the number of displaced this year: almost 809,000.
A meeting of South Korea's National Security Council was set to be held later Thursday, the presidential office Cheong Wa Dae said, apparently to discuss North Korea's fresh threat to stage a missile provocation against the United States.
While European stocks.STOXXE have seen robust inflows in the wake of the French elections, their performance have lagged their USA rivals since mid June. TMX Group Ltd was up 3.5 percent to C$68.23, while Quebecor Inc added 2.9 percent to C$44.60. Humana rose $3.59, or 1.4 percent, to $253.81.
On the currency markets, the pound was down to a three-week low against the USA dollar but mainly due to earlier disappointing output and trade data.
Gold hit its highest in nearly two months after Trump added to the geopolitical anxiety by boasting of the strength of the USA nuclear arsenal.
The news was also greeted with dismay by traders in Asia, with Tokyo down 1.3 percent, Hong Kong losing 0.4 percent and Seoul registering a 1.1-percent decline. TripAdvisor shares shed $2.70, or 6.8 percent, to $36.85. Its shares slid $9.77, or 5.3 percent, to $174.02.
The Swiss franc reversed a two-week losing streak, rising rose 1.12 per cent versus the greenback at 0.96 per dollar.
Severe thunderstorm watch (again)
Forecasters say severe storms will move from the Oklahoma Panhandle and northwestern Oklahoma Thursday night. The high temperature on Saturday is expected to be 82, when afternoon rain and thunderstorms are expected.
USA crude CLcv1 rose 1.08 percent to $49.70 per barrel and Brent LCOcv1 was last at $52.78, up 1.23 percent on the day.
CURRENCIES: The dollar fell to 109.87 yen from 110.48 yen late Tuesday.
After ending Tuesday's trading modestly lower, stocks saw continued weakness during trading on Wednesday.
ENERGY: Benchmark U.S. crude lost 23 cents to $48.94 per barrel in electronic trading on the New York Mercantile Exchange. The strength in the sector comes as gold for December delivery is jumping $11.30 to $1,290.60 an ounce. The euro edged down to $1.1726 from $1.1751.
10-Year Treasury Yield 2.24% -0.01%.
CNMI governor backs Trump's stance on North Korea
The island was first populated about 4,000 years ago by the ancestors of the Chamorros , still the island's largest ethnic group. Another option is Aegis Ashore, a naval tracking and missile defense system that has been converted to a land defense battery.