"I decided that it was time to come back in and really rejoin the debate"

“We need to stimulate a debate about where the country is,” he said.

He suggested that Clinton’s tenure as secretary of state wasn’t all it’s cracked up to be, telling a radio interviewer it would “take up the whole show” for him to critique her record.

“I think there’s time to have that discussion later,” he said.

He also disagreed with suggestions from Clinton and others that the U.S. should have moved more quickly to arm moderate rebel groups in Syria after the country descended into civil war several years ago.

“I can’t understand why people would have supported the notion of arming certain groups inside Syria a couple of years ago,” he said. “I say that not only as someone who has spent a lot of time working on foreign policy but as a journalist in Beirut in 1983 when the word I got from Marines on the ground was: ‘Never get involved in a five-sided argument.'”