Derek Chollet, a key figure on the Obama administration's national security team, told his staff Wednesday that he'll be leaving the Pentagon in January.
As assistant secretary of defense for international security affairs, Chollet advises Defense Secretary Chuck Hagel on policy issues related to Europe, the Middle East, Africa, and the Western Hemisphere. He also has oversight for security cooperation programs, including foreign military sales, in these regions. His decision hadn't been made public until now.
Chollet, well regarded within both the White House and the Pentagon, had long been seen as a front-runner to be the next undersecretary of defense for policy, the Defense Department's No. 3 job.
After nearly six years serving in Barack Obama's administration, Chollet told staff Wednesday, July 30, that it's time for him to devote his energy to other endeavors, including his family. His departure is sure to spark speculation that Chollet, like other prominent Democratic national security officials, may be leaving to recharge his batteries before taking a senior post in a potential Hillary Clinton administration.
"I also intend to remain very engaged in the issues of the day and the important debate about America's role in the world, but more on that later," he said in an email to staff obtained by Foreign Policy.
A defense official said Chollet would remain active after he left. "I expect you'll see him writing a book and lending his voice on any number of topics," the official said. "He's got a lot of credibility."
The international security affairs office will also see a few more personnel changes in the next month.
Elissa Slotkin will be returning in August as the principal deputy assistant secretary of defense for international security affairs. She had been performing the duties of the principal deputy undersecretary of defense for policy while Brian McKeon waited for the Senate to confirm him to that post, which it finally did on Monday.
Lisa Kenna, a career foreign service officer whose last job was as a political counselor at the U.S. Embassy in Jordan, will also be joining the international security affairs office in August as a senior advisor. Before Jordan, she was on the National Security Council staff at the White House.
"Lisa will provide much needed bandwidth in the front office, helping all of us manage multiple crises as well as special projects that are beyond the in-box," Chollet said in his email.
As for who will replace Chollet, it remains to be seen, but Slotkin is looking like an obvious candidate.
"No decision has been made on a replacement, but with Elissa going back to ISA [international security affairs] as the principal deputy, she would obviously be on the shortlist of contenders," the defense official said. "It's worth noting that over the last year, filling in as she did in the policy front office, she has become a close and trusted advisor to the secretary."
Chollet's goodbye email to staff reveals how busy a time it has been inside the Pentagon's policy office.
"Whether it concerns Ukraine, Gaza, Syria, Iraq, Libya, the NATO summit, the [European Reassurance Initiative/Combating Terrorism Partnership Fund], the African leaders summit, or the Unaccompanied Children issue, we have been at the center of the action, and you have really stepped up," Chollet said.
Before his Pentagon job, Chollet worked at the White House as special assistant to the president and senior director for strategic planning on the National Security Council staff. From February 2009 to 2011, Chollet served in the State Department as the principal deputy director of the secretary of state's policy planning staff. From November 2008 to January 2009, he was a member of the Obama-Biden presidential transition team.
He also has connections to the Center for a New American Security, where he was a senior fellow.
During Bill Clinton's first administration, he served as chief speechwriter for U.S. Ambassador to the United Nations Richard Holbrooke and as special advisor to Deputy Secretary of State Strobe Talbott.
From 2002 to 2004, Chollet was foreign-policy advisor to U.S. Senator John Edwards (D-N.C.).
Gordon Lubold contributed to this report.
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