The attack raised ISIS-K’s international profile, and positioned it both as a major threat to the Taliban’s ability to govern the country and, according to American officials, as the most imminent terrorist risk to the United States coming out of Afghanistan.

“The group has gained some notoriety in a way that could be quite compelling for them on the transnational stage,” Christine Abizaid, the director of the National Counterterrorism Center, said in October at a national security conference in Sea Island, Ga. “At the same time, they’re fighting the Taliban. How that force-on-force engagement in Afghanistan will go will have some defining characteristics about what the transnational threat looks like.”

In October, Colin H. Kahl, the under secretary of defense for policy, told the Senate Armed Services Committee that ISIS-K could be able to attack the United States sometime in 2022. “We could see ISIS-K generate that capability in somewhere between six and twelve months,” he said.