Charles G. Wolf, whose wife Katherine Wolf was killed in the World Trade Center in the attacks on Sept. 11, 2001, said he was thrilled to hear about the U.S. killing of al-Qaida leader Ayman al-Zawahri.
Wolf was visiting the 9/11 Memorial in lower Manhattan on Tuesday, a day after President Joe Biden announced that al-Zawahri was killed in a U.S. drone strike in Kabul.
Biden said the operation delivered justice and hopefully "one more measure of closure" to the families of the Sept. 11 attacks on the United States.
The president said in an evening address from the White House that U.S. intelligence officials tracked al-Zawahri to a home in downtown Kabul where he was hiding out with his family. The president approved the operation last week and it was carried out Sunday.
Al-Zawahri and the better-known Osama bin Laden plotted the 9/11 attacks that brought many ordinary Americans their first knowledge of al-Qaida. Bin Laden was killed in Pakistan on May 2, 2011, in operation carried out by U.S. Navy SEALs after a nearly decade-long hunt.
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The strike was carried out by the CIA, according to five people familiar with the matter who spoke on the condition of anonymity.
Al-Zawahri's death eliminates the figure who more than anyone shaped al-Qaida, first as bin Laden's deputy since 1998, then as his successor. Together, he and bin Laden turned the jihadi movement's guns to target the United States, carrying out the deadliest attack ever on American soil — the Sept. 11 suicide hijackings.