SPY EYES

Hillary Clinton called the Benghazi terror attack the “biggest regret” of her tenure as secretary of State on Monday, a message she's expected to emphasize, as she ponders a 2016 White House run.

“My biggest, you know, regret is what happened in Benghazi,” Clinton said when asked to identify “do-overs” of her time as America's top diplomat, during her keynote appearance before the National Automobile Dealers Association in New Orleans. [WATCH VIDEO]

“I mean, you know, you make these choices based on imperfect information,” she said. “And you make them to, as we say, the best of your ability. But that doesn't mean that there's not going to be unforeseen consequences, unpredictable twists and turns.”

This isn't the first time Clinton makes such comments. She mentioned Benghazi during a global town hall with young diplomats conducted via satellite last year, suggesting her reaction to the attack would feature prominently in her upcoming memoirs.

“Certainly the loss of American lives in Benghazi was something that I deeply regret and am working hard to make sure we do everything we can to prevent,” she said during last year's event at the Newseum in Washington, D.C.

Republicans have hammered Clinton over the death of Stevens, the U.S. ambassador to Libya, and three other Americans in a Sept. 11, 2012, terrorist attack.

They've used the episode to chip away at her record on national security. An internal review of the attack faulted the State Department for failing to provide better security at the U.S. diplomatic mission, but Republicans say Clinton has unfairly escaped blame.

Clinton slammed her critics at a Senate hearing last year — she famously demanded to know, “What difference does it make?” what prompted the attack — but has since adopted a different tone.