The Biden administration is holding out the CIA operation that killed Al Qaeda’s leader as a monumental strike against the global terror network responsible for the September 11, 2001, attacks. Yet there’s a downside, too.

The drone strike also is putting into stark relief the mounting evidence that Afghanistan has once again become an active staging ground for Islamic terror groups looking to attack the West.

The operation against the Al Qaeda leader, carried out over the weekend after at least six months spent monitoring movements by Ayman al-Zawahri and his family, came just weeks before the one-year anniversary of the chaotic U.S. withdrawal from Afghanistan.

The president is making the case that the operation shows Americans at home and allies abroad that the United States hasn’t lost focus — or the ability to strike terrorists in the region — and validates its decision to end two decades of fighting in Afghanistan with its withdrawal.

Yet as details of the operation continue to emerge, the administration has also disclosed troubling evidence of Al Qaeda’s presence and of the Taliban once again offering refuge to the group that was behind the 9/11 attacks on the United States.

White House officials believe that senior members of the Haqqani Network, an Islamist terror group with strong ties to the Taliban, were aware that al-Zawahri was in Kabul. The American national security advisor, Jake Sullivan, said that while al-Zawahri wasn’t involved in day-to-day planning at the time of his killing, he continued to play an active role in directing Al Qaeda and posed “a severe threat” against the U.S. and American citizens.

The Senate Republican leader, Mitch McConnell, was quick to congratulate President Biden on the operation, but also made the case that it “further indicates that Afghanistan is again becoming a major thicket of terrorist activity following the president’s decision to withdraw U.S. forces.”

“Killing al-Zawahri is a success, but the underlying resurgence of Al Qaeda terrorists into Afghanistan is a growing threat that was foreseeable and avoidable,” Mr. McConnell said. “The administration needs a comprehensive plan to rebuild our capacity to combat it.”

On Wednesday Senator Cotton entered the fray by mocking the New York Times for having allowed a Taliban leader, Sirajuddin Haqqani, to pen an op-ed for the newspaper in 2020. The Times “really needs to improve its process for accepting op-eds,” the senator tweeted, in part. A conservative commentator, Noah Blum, quipped on social media, “Can’t believe Ayman Al-Zawahiri was staying at the home of New York Times contributor Sirajuddin Haqqani.”

That al-Zawahri was living in a Kabul neighborhood and not in rural Afghanistan, as previously believed, “tells you that he got really comfortable” under the protection of the Taliban, the director of research at The Soufan Group, a global intelligence and security firm, Colin Clarke, said.

“These entities work hand in glove,” Mr. Clarke said of the Taliban and Al Qaeda.

“Zawahri’s presence in post-withdrawal Afghanistan suggests that, as feared, the Taliban is once more granting safe haven to the leaders of Al Qaeda — a group with which it has never broken,” an ambassador-at-large and coordinator for counterterrorism during the Trump administration who is now a senior fellow at the Atlantic Council, Nathan Sales, said.

A retired Marine general who until earlier this year was the top American military officer in the Middle East, Frank McKenzie, said the U.S. has noted an effort by Al Qaeda to restore training camps in Afghanistan.

“I see nothing happening in Afghanistan now that tells me that the Taliban are determined to prevent that from happening,” he said in an interview.

Since the American troop withdrawal, American military leaders have said America’s ability to monitor and strike a target in the country would be difficult but not impossible.

Since news of the lethal drone strike broke, the State Department has updated its Worldwide Caution, warning U.S. citizens traveling abroad that “there is a higher potential for anti-American violence given the death of Ayman al-Zawahri.”