Hillary Clinton participates in a Commander in Chief Forum in New York on Sept. 7. (Photo by Melina Mara/The Washington Post)

Democratic presidential nominee Hillary Clinton acknowledged that emails she sent or received as secretary of state contained references to the CIA’s drone program, but she defended her handling of communications about the classified operations.

Pressed during an NBC forum on national security about whether there were email references to the strikes, Clinton appeared to hesitate.

“Yes, because — of course, there were no discussions of any of the covert actions in process being determined about whether or not to go forward,” she said. “But every part of our government had to deal with questions, and the secretary of state’s office was first and foremost. So there are ways of talking about the drone program.”

Clinton said some email communication about the strikes was necessary because of the diplomatic ramifications of the program and the fact that government officials do not always have access to classified networks.

“I just respectfully point to the hundreds of experienced foreign policy experts, diplomats, defense officials who were communicating information on the unclassified system, because it was necessary to answer questions and to be able publicly to go as far as we could, which was not acknowledging the program,” she said.

Clinton’s response reflects the uncomfortable duality of the Obama administration’s reliance on overseas drone strikes. After President Obama took office in 2009, the pace of strikes increased significantly, and the covert program became a central part of U.S. counterterrorism strategy.

Officially, the program has remained a secret, despite the extensive news reports that have documented the strikes. Many U.S. officials believe the cover of secrecy makes it easier for partner nations to accept the strikes, and also avoids some of the disclosures that would come along with strikes by the military.

But in practice, the strikes have been widely acknowledged by government officials. Obama himself has addressed the drone program and has sought to increase transparency about civilians killed in overseas counter-terrorism activities. Last year, he apologized for a CIA drone strike that killed an American hostage in Pakistan.

As secretary of state, Clinton played a key role in defusing tensions with Pakistan, which was the focal point of the CIA drone operations at the time.

Local journalists in Pakistan routinely reported on drone strikes in the country’s tribal areas, but the operations were highly controversial.

“I would be asked in a public setting, in an interview, about it. It was known to have happened,” Clinton said. “We had to have an answer that did not move into classified area. And I think we handled that appropriately.”

The number of U.S. drone strikes in Pakistan has dropped significantly since its peak in 2010.

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