Former Florida Governor Jeb Bush speaks to guests at a luncheon hosted by the Chicago Council on Global Affairs on Feb. 18, 2015, in Chicago.
CNN  — 

Jeb Bush said on Wednesday that the National Security Agency’s controversial domestic surveillance program is “hugely important” and expressed bewilderment at those who rail against the effort.

“For the life of me I don’t understand, the debate has gotten off track,” the former Florida governor said in a speech at the Chicago Council on Global Affairs, breaking from his prepared remarks.

“We do protect our civil liberties, but this is a hugely important program to use these technologies to keep us safe,” he said.

READ: Rand Paul opposes Senate NSA reform

He described the program – which stores information like phone numbers and the time and duration of calls – as “responsible intelligence gathering and analysis” that “contributes to awareness of potential terror cells and interdiction efforts on a global scale.”

It started under the administration of his brother, former President George W. Bush, after the 9/11 attacks.

The seemingly candid moment marked what could become a flash point in the Republican presidential race. Sen. Rand Paul sued the Obama administration last year over the issue, arguing the program violates civil liberties.

While the lawsuit has stalled, the Kentucky Republican has made it clear that ending the NSA program will be a key plank in his platform if he runs for president.

“I plan on continuing to be a big thorn in the side of big government who wants to invade your privacy, and I’m going to do everything I can to try to stop it,” Paul said last week at a libertarian leaning conference hosted by LincolnLabs.

Sen. Ted Cruz of Texas, who’s also considering a presidential run, voted to advance a bill last year that would reform the NSA. The measure, however, failed to move farther in the Senate, in part because Paul voted against it, saying the reform didn’t go far enough.

According to a Washington Post survey last month, more than 6-in-10 Americans say it’s more important for the government to investigate possible terrorist threats, even if at the risk of violating personal privacy, while 34% disagree.