WASHINGTON (CBSDC/AP) — President Obama revealed clearer guidelines for drone strikes during a counterterrorism policy speech Thursday.

Speaking before the National Defense University in Washington, D.C., Obama says he wants to “facilitate transparency” about targeted drone strikes.

“For the record, I do not believe it would be constitutional for the government to target and kill any U.S. citizen – with a drone, or a shotgun – without due process,” Obama said. “Nor should any president deploy armed drones over U.S. soil.”

Obama stood by his decision to target and kill al-Qaeda terrorist Anwar al-Awlaki – an American — in a drone strike in Yemen, though.

“When a U.S. citizen goes abroad to wage war against America – and is actively plotting to kill U.S. citizens — and when neither the United States, nor our partners are in a position to capture him before he carries out a plot – his citizenship should no more serve as a shield than a sniper shooting down on an innocent crowd should be protected from a swat team,” Obama said, adding that he would have been “derelict in his duty” if the U.S. did not take action against al-Awlaki.

Obama talked about the questions and concerns about drone strikes, specifically the loss of lives among civilians that are killed in targeted strikes on terrorists in Pakistan and Afghanistan.

“America does not take strikes when we have the ability to capture individual terrorists – our preference is always to detain, interrogate, and prosecute them,” Obama said, adding that “there must be near-certainty that no civilians will be killed” before any drone strike is taken.

Obama defended drone strikes as legal and a necessity.

“Where foreign governments cannot or will not effectively stop terrorism in their territory, the primary alternative to targeted, lethal action is the use of conventional military options,” Obama said. “As I’ve said, even small Special Operations carry enormous risks. Conventional airpower or missiles are far less precise than drones, and likely to cause more civilian casualties and local outrage. “

In his speech, Obama called on his administration to “review proposals to extend oversight of lethal actions outside of warzones that go beyond our reporting to Congress.”

The president brought up options of a special court to authorize lethal action or the establishment of an independent oversight board in the executive branch.

Ahead of the address, Obama signed new “presidential policy guidelines” aimed at illustrating more clearly to Congress and the public the standards the U.S. applies before carrying out drone attacks. Officials said the guidelines include not using strikes when the targeted people can be captured, either by the U.S. or a foreign government, relying on drones only when the target poses an “imminent” threat and establishing a preference for giving the military control of the drone program.

The administration revealed Wednesday that four Americans have been killed in overseas drone strikes.

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