By Terry Frieden

Attorney General Eric Holder on Monday defended the targeted killing of U.S. citizens abroad who are suspected of plotting to kill Americans, rejecting critics' arguments that those strikes amount to assassinations.

While not referring directly to the government's drone attack on U.S.-born Anwar al-Awlaki in Yemen last year, Holder was unflinching in providing publicly for the first time the Justice Department's legal justification for using lethal force, saying attacks like the strike that killed al-Awlaki fell within "our laws and values."

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"Let me be clear: An operation using lethal force in a foreign country, targeted against a U.S. citizen who is a senior operational leader of al Qaeda or associated force, and who is actively engaged in planning to kill Americans, would be lawful," he said.

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The attorney general's speech to an audience at the Northwestern University Law School in Chicago marked his most expansive comments on the subject of deadly attacks against Americans since his lawyers in the Office of Legal Counsel wrote a still-secret opinion declaring such lethal attacks are legal and justifiable.

But he said three conditions must exist. The U.S. government must have determined that the individual poses an imminent threat of violent attack against America; capture of the suspect is not feasible; and the operation would be conducted within the principles of the law of war.

Holder argued that al Qaeda has the ability to spring surprise attacks and is considered to be continuously planning against to attack on America. Therefore, the law allows for striking even before the "precise time, place, and manner of an attack becomes clear."

"Such a requirement would create an unacceptably high risk that our efforts would fail, and that Americans would be killed," he said.

Holder rejected the charge that the deadly operations violate the government's ban on assassinations and dismissed the notion the strikes fit the definition of assassination at all.

"Some have called such operations 'assassinations.' They are not, and the use of that loaded term is misplaced," he said. "Assassination are unlawful killings," while killings under the conditions he outlined would be lawful.

Holder also took issue with those who have charged the government agencies must get permission from a federal court before taking action against an al Qaeda target.

"This is simply not accurate," Holder said. "Due process and judicial process are not one and the same, particularly when it comes to national security. The Constitution guarantees due process, not judicial process."

Al-Awlaki and another American, Samir Khan, were killed in September when a drone operated jointly by the CIA and a military unit destroyed a vehicle in which the men were riding in Yemen. Al-Awlaki, who U.S. intelligence officials have said was an operational planner for attacks, was the target of that strike.

Khan was traveling with al-Awlaki and was not specifically targeted.

Court documents show that Umar Farouk AbdulMutallab, the so-called "Underwear Bomber," told U.S. authorities that al-Awlaki had played a major role in the plot to blow up a commercial airliner en route to Detroit on Christmas Day 2009. President Obama later said al-Awlaki had "directed the failed attempt."

The American Civil Liberties Union, which filed an unsuccessful lawsuit challenging the administration's drone program on behalf of al-Awlaki's father, said the speech was "a gesture towards additional transparency," but continued to object to the legal rationale.

"Few things are as dangerous to American liberty as the proposition that the government should be able to kill citizens anywhere in the world on the basis of legal standards and evidence that are never submitted to a court, either before or after the fact," Hina Shamsi, the director of ACLU's National Security Project, said in an e-mailed statement. "Anyone willing to trust President Obama with the power to secretly declare an American citizen an enemy of the state and order his extrajudicial killing should ask whether they would be willing to trust the next president with that dangerous power."

Democratic Senator Ron Wyden said Holder's speech left questions unanswered.

“For example, the government should explain exactly how much evidence the President needs in order to decide that a particular American is part of a terrorist group," Wyden said in a statement released on Monday. "It is also unclear to me whether individual Americans must be given the opportunity to surrender before lethal force is used against them. And I’m particularly concerned that the geographic boundaries of this authority have not been clearly laid out. Based on what I’ve heard so far, I can’t tell whether or not the Justice Department’s legal arguments would allow the President to order intelligence agencies to kill an American inside the United States."

Holder also used the speech to defend the use of civilian courts to try terrorists, noting numerous successful prosecutions.

"The calls that I've heard to ban the use of civilian courts in prosecutions of terrorism-related activity are so baffling, and ultimately are so dangerous. These calls ignore reality," Holder said. "If heeded, they would significantly weaken - in fact, they would cripple - our ability to incapacitate and punish those who attempt do us harm."

And Holder indicated more targeted killings are possible.

"When such individuals take up arms against this country, and join al Qaeda in plotting attacks designed to kill their fellow Americans, there may be only one realistic and appropriate response," Holder said. "We must take steps to stop them in full accordance with the Constitution. In this hour of danger, we simply cannot afford to wait until deadly plans are carried out, and we will not."

He concluded, "This is an indicator of our times, not a departure from our laws and values."

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