Asserting that the US faced tough threats from the American recruits of al Qaeda, a top Obama official has said the government has "clear authority" to kill its citizens abroad who are believed to be holding a terrorist threat.
"Given the nature of how terrorists act and where they tend to hide, it may not always be feasible to capture a United States citizen terrorist who presents an imminent threat of violent attack," US Attorney General Eric Holder, said.
"In that case, our government has the clear authority to defend the United States with lethal force," Holder said in his remarks at the Northwestern University School of Law, in Chicago.
Holder said the argument by some that the US President is required to get permission from a federal court before taking action against a US citizen who is a senior operational leader of al Qaeda or associated forces is not accurate.
"Due process" and "judicial process" are not one and the same, particularly when it comes to national security, he said, adding that the Constitution guarantees due process, not judicial process.
The Attorney General said the unfortunate reality is that US will likely continue to face terrorist threats that at times originate with its own citizens.
"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. 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 said.
Holder said any such use of lethal force by the US will comply with the four fundamental war principles governing the use of force -- the principle of necessity that requires that the target have definite military value, the principle of distinction that requires that only lawful targets may be targeted intentionally, the principle of proportionality of use of force and the principle of humanity that requires use weapons that will not inflict unnecessary suffering.
"These principles do not forbid the use of stealth or technologically advanced weapons. In fact, the use of advanced weapons may help to ensure that the best intelligence is available for planning and carrying out operations, and that the risk of civilian casualties can be minimised or avoided altogether," Holder said.
The Attorney General said 9/11 has shown that al Qaeda has demonstrated the ability to strike with little or no notice and to cause devastating casualties.
"Its leaders are continually planning attacks against the United States, and they do not behave like a traditional military uniforms, carrying arms openly, or massing forces in preparation for an attack," he said.
"Given these facts, the Constitution does not require the President to delay action until some theoretical end-stage of planning -- when the precise time, place, and manner of an attack become clear.
"Such a requirement would create an unacceptably high risk that our efforts would fail, and that Americans would be killed," he said.
"Whether the capture of a US citizen terrorist is feasible is a fact-specific, and potentially time-sensitive, question. It may depend on, among other things, whether capture can be accomplished in the window of time available to prevent an attack and without undue risk to civilians or to US personnel," he said.