Washington: President Barack Obama has defended his country's controversial drone attacks as legal, effective and a necessary tool in an evolving US counterterrorism policy.
But addressing an audience at the National Defence University on Thursday, he acknowledged the targeted strikes are no "cure-all" and said he is haunted by the civilians unintentionally killed.
Obama framed his speech as an attempt to redefine the nature and scope of terror threats facing the US, noting the weakening of al-Qaeda and the impending end of the US war in Afghanistan.
"So America is at a crossroads. We must define the nature and the scope of the struggle, or else it will define us," said Obama, saying that threats to diplomatic facilities must be dealt with as well as "homegrown extremists".