When Anwar al-Awlaki walked out of a home in the northern Yemeni town of Khashef and stepped into a Toyota pickup Friday morning, he had finally entered the crosshairs of an armed drone that flew noiselessly overhead.
Few violent jihadists had been hunted more assiduously than Awlaki, a US citizen who through his reported role in a succession of plots targeting the United States had risen near the top of the list of American terrorist targets. Yet he had evaded several airstrikes aimed at him.
Friday's CIA drone strike, which killed Awlaki and a second American, came after days of careful surveillance and many months of searching.
It stripped al Qaeda in the Arabian Peninsula of two of its major propagandists and proponents of hitting Western targets, according to intelligence officials and terrorism experts.
But those individuals also cautioned that the group, which has a number of prominent members with a deep hatred for the US, will continue to seize any opportunity to wound the West.
"Eliminating any single person doesn't have a game-changing impact, and this won't. But it's a significant strike against al Qaeda," said Rep Adam B Schiff (Democrat California), a member of the House intelligence committee.
Awlaki "had an almost unique ability to reach out to Westerners - he was good with technology, he was a good propagandist, he understood Western culture, and he could attract people that could travel with US passports."
US officials said that Awlaki's operational role and the imminence of the threat he posed led them in early 2010 to place him on a capture or kill list. Yet he proved to be an elusive target.
Awlaki, who was born in New Mexico, was the scion of a powerful tribe in southern Yemen and was presumed to be hiding in the protective embrace of his extended family.
But a senior US official said Awlaki, 40, seldom lived in the south, even though his tribe, the Awlak, wielded influence there.
He moved between several locations in the provinces of Jawf and Marib, two al Qaeda strongholds east of the capital, Sanaa.
"He occasionally went south, but generally speaking, his base was in the north, in Jawf and Marib," said the official, speaking on the condition of anonymity.
"The Awlak tribe is in the south, but he wasn't there. He was up north."
The official said Awlaki was meticulous about leaving no electronic fingerprints. He didn't talk on the phone or take other actions that would have betrayed his position.
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