In a letter to congressional leaders Wednesday, Attorney General Eric Holder formally acknowledged that four American citizens had been killed by U.S. drone strikes abroad, including al-Qaida-affiliated cleric Anwar al-Awlaki.

The New York Times:

The American responsibility for Mr. Awlaki’s death has been widely reported, but the administration had until now refused to confirm or deny it.

The letter also said that the United States had killed three other Americans: Samir Khan, who was killed in the same strike; Mr. Awlaki’s son Abdulrahman al-Awlaki, who was also killed in Yemen; and Jude Mohammed, who was killed in a strike in Pakistan.

…Mr. Holder, in a speech at Northwestern University Law School last year, laid out the administration’s basic legal thinking that American citizens who are deemed to be operational terrorists, who pose an “imminent threat of violent attack” and whose capture is infeasible may be targeted. That abstract legal thinking — including an elastic definition of what counts as “imminent” — was further laid out in an unclassified white paper provided to Congress last year, which was leaked earlier this year.

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