What the Afghan government’s collapse might mean for the U.S. stock market

After 20 years in the shadows, the Taliban have returned to power in Afghanistan, raising questions about stability in the Middle East and stoking some potential unrest in U.S. financial markets, amid a weekend that was rife with political developments.

However, the impact to the stock market, with the Dow Jones Industrial Average DJIA, 0.31%, the S&P 500 index SPX, 0.26% and the Nasdaq Composite Index COMP, -0.20% trading at or near record highs, is unclear.

“It’s a terrible situation for those U.S. folks who are still there,” J.J. Kinahan, chief market strategist at TD Ameritrade, told MarketWatch in emailed...