Every US president since 2001 has delivered a sombre White House address proclaiming a major victory in America's continuing "war on terror".
For George W Bush, it was the 2003 capture of Saddam Hussain in Iraq. Barack Obama in 2011 announced the special forces raid in Pakistan that killed Osama bin Laden. Then came Donald Trump, who in 2019 boasted of the killing of Abu Bakr Al Baghdadi, the ISIS leader that Mr Trump said had "died like a dog".
Late on Monday, it was President Joe Biden's turn.
"Justice has been delivered. This terrorist leader is no more," Mr Biden said.
"No matter how long it takes, no matter where you hide, if you are a threat to our people, the United States will find you and take you out."
For the Biden administration, the timing of the strike is opportune. It comes as officials are scrambling to reset the narrative surrounding the chaotic final weeks of the US-led war in Afghanistan.
Afghanistan "can't be a launching pad against the United States," Mr Biden said in his address.
"This operation is a clear demonstration that we will, we can, and we'll always make good on the solemn pledge."
Twenty years of western military intervention that killed tens of thousands of civilians and combatants, and led to trillions of dollars spent in aid and war-fighting, culminated with the Taliban once more in control of the country.
Early on Tuesday, Mr Biden's National Security Adviser Jake Sullivan said Al Zawahiri's death validates the president's decision to end America's longest war.
The president "said we would be able to continue to target and take out terrorists in Afghanistan without troops on the ground. And over this weekend, with this swift and decisive action that he ordered, he delivered on that promise," Mr Sullivan told NBC's Today programme.
The extent to which the US could monitor Al Qaeda and other terror groups in Afghanistan has been an open question since the withdrawal.
The US has claimed it maintains an "over-the-horizon" strike capability, meaning it can launch attacks from aircraft carriers or other nations. Sunday's strike against Al Zawahiri demonstrates this continuing ability, but it is notable that this is the first such strike in almost a year.
Pundits in Washington were quick to laud the operation and said Mr Biden deserved a victory lap. Even staunchly anti-Biden Fox News called the killing "a huge, huge win for the US."
But some analysts were wary of reading too much into the longer-term ramifications.
Nathan Sales, a senior fellow at the Atlantic Council's Scowcroft Middle East Security Initiative and Middle East Programmes, said it is unknown if the strike can be replicated.
"It remains to be seen whether the administration has the capability or intent to systematically dismantle the terror networks in (Afghanistan) that threaten us," he said.
"Until we know more, we should resist the urge to see the strike as a vindication of 'over-the-horizon' counterterrorism."
And the mere fact Al Zawahiri had been living in a central Kabul safe house under the Taliban's noses is telling.
It shows leaders of the hard-line group were never serious about vague commitments to the Trump administration in 2020 "not to co-operate with groups or individuals threatening the security of the United States and its allies.”
It also undermines a central justification that Mr Biden gave for pulling out of Afghanistan.
"We went to Afghanistan for the express purpose of getting rid of al Qaeda in Afghanistan," he said on August 20, 2021. "And we did."
As Mr Sullivan confirmed, senior members of the Taliban's Haqqani network knew Al Zawahiri was living in Kabul. The home itself reportedly belonged to a top aide to Sirajuddin Haqqani, the deputy Taliban leader.
The killing of Al Zawahiri will be sold as a counterterrorism success, said Bill Roggio, a senior fellow at the Foundation for the Defence of Democracies.
"But that narrative masks the undeniable truth that Taliban-controlled Afghanistan is a safe have for Al Qaeda," he said.
Mr Biden can enjoy the moment, which comes after surprising developments at home that have breathed life into his stalled legislative agenda.
But as the one-year anniversary approaches, it is unclear the extent to which Al Zawahiri's killing can deflect from the Biden administration's humiliating end to the war in Afghanistan.
And how much the American public, still grappling with record inflation and rising borrowing costs, will care before the November midterm elections is an open question.