Former Florida Gov. Jeb Bush, who is seriously considering a run for the White House in 2016, said Wednesday that the National Security Agency’s program that collects bulk telephone records was “hugely important,” throwing his support behind the practice as Congress debates whether to reauthorize or limit it.

At an event on foreign policy hosted by the Chicago Council on Global Affairs, Mr. Bush, a Republican, said, “For the life of me, I don’t understand the debate” over the metadata program.