In his old job, Carter said he used email all the time.
“Now, in this job, I use a different way of operating,” he said, noting that on the occasions he does send email, he keeps them short.
"In general, my staff uses messages, and of course we send copious messages back and forth around the world," Carter said. "For myself, I am very careful."
The office of the Chairman of the Joint Chiefs of Staff in the Pentagon nearly experienced a serious breach recently when a staff member opened an email he shouldn't have, Carter said.
"The department as a whole uses email and all kinds of other electronic aids all day and we need to protect that," he said.