Hillary Clinton says she gave “very direct instructions” to security experts during the 2012 Benghazi attack in an effort to secure the U.S. mission.

“I’m not equipped to sit and look at blueprints, to determine where the blast walls need to be or where the reinforcements need to be,” she said in an excerpt for the ABC News interview airing Monday night. “That’s why we hire people who have that expertise.”

Host Diane Sawyer asked Clinton if there was anything she could have “personally” done to protect the Americans in Benghazi.

“What I did was give very direct instructions” to “the people who have the expertise and experience in security,” Clinton said. “That is personal.”

U.S. Ambassador Christopher Stevens and three other U.S. citizens died in the attack. Clinton wrote about Benghazi in her memoir Hard Choices, which hits bookstores on Tuesday.

Clinton declined to say whether she is willing to testify on Benghazi before the new House select committee investigating the attack.