WASHINGTON (Reuters) - The U.S. campaign of drone strikes to kill militants in other countries is legal under international law, President Barack Obama's counterterrorism adviser insisted on Monday in a rare public admission and justification of the controversial tactic.
John Brennan's speech, on the eve of the one-year anniversary of the U.S. killing of al Qaeda leader Osama bin Laden in a raid in Pakistan, was remarkable in that U.S. officials in public rarely discuss the drone program, which has for years been considered a covert CIA operation.
The bin Laden commando raid and drone strikes have severely strained U.S. relations with Pakistan. But the frayed ties have not stopped the United States from pursuing militants with the unmanned aircraft that can be remotely piloted from hundreds or thousands of miles away.
Last weekend, a U.S. drone strike killed four suspected militants in Pakistan's North Waziristan tribal region, despite the recent demand by a Pakistani parliamentary committee that such operations end.
"I'm here today because President Obama has instructed us to be more open with the American people about these efforts," Brennan said in a speech at the Woodrow Wilson International Center for Scholars, a Washington think tank.
"These targeted strikes are legal," he said, citing legal opinions from the administration, the U.S. Constitution and the Authorization for Use of Military Force passed by Congress after the September 11, 2001 attacks.
"As a matter of international law, the United States is in an armed conflict with al Qaeda, the Taliban, and associated forces, in response to the 9/11 attacks, and we may also use force consistent with our inherent right of national self-defense," Brennan said.
"There is nothing in international law that bans the use of remotely piloted aircraft for this purpose or that prohibits us from using lethal force against our enemies outside of an active battlefield, at least when the country involved consents or is unable or unwilling to take action against the threat," he said.
ACLU SAYS 'UNLAWFUL'
The killing of suspected militants, including American citizens overseas, by U.S. drones has been criticized by human rights and civil liberties groups.
The American Civil Liberties Union filed a lawsuit earlier this year seeking Justice Department memos justifying the targeted killings, such as the strike against dual U.S.-Yemeni citizen Anwar al-Awlaki last year.
Brennan's speech was important as an "unambiguous acknowledgement" of the program and the clearest explanation so far of administration legal views, the ACLU said in a statement.
"We continue to believe, based on the information available, that the program itself is not just unlawful but dangerous," Hina Shamsi, director of the ACLU National Security Project, said. "It is dangerous to characterize the entire planet as a battlefield."
Brennan said criticism that the United States prefers killing militants over capturing them is wrong. "It is our preference to capture suspected terrorists whenever feasible," he said.
"We do not use force whenever we want, wherever we want," he said. "International legal principles, including respect for a state's sovereignty and the laws of war, impose constraints. The United States of America respects national sovereignty and international law."
He said the United States was mindful that it was setting precedents for other countries that possess this technology or are seeking it.
"If we want other nations to use these technologies responsibly, we must use them responsibly," Brennan said. "We cannot expect of others what we will not do ourselves. President Obama has therefore demanded that we hold ourselves to the highest possible standards - that, at every step, we be as thorough and deliberate as possible."
The issue of targeted strikes raises "profound moral questions," Brennan said. "If anyone in government who works in this area tells you they haven't struggled with this, then they haven't spent much time thinking about it. I know I have, and I will continue to struggle with it as long as I remain involved in counterterrorism."
(Additional reporting By Matt Spetalnick; Editing by Vicki Allen)