Will Afghanistan become a haven for terrorism again?

When the United States invaded Afghanistan 20 years ago, the primary mission was to root out the al-Qaida terrorists responsible for the Sept. 11 attacks and the Taliban regime that had given them safe harbor. The recent withdrawal of U.S. forces from the country, which allowed the Taliban to swiftly regain control, has sparked debate over whether Afghanistan could once again become a staging ground for extremists to plan acts of terror in the U.S. and around the world.

In his address to the nation on Monday, President Biden called...