President Obama's longest-serving foreign policy adviser, Mark Lippert, has decided to return to active duty in the Navy SEALs, the White House announced today. Lippert, 36, is chief of staff to the National Security Council. He has presided over an intricate and occasionally thorny reconfiguration of the 200 person NSC staff to better reflect Obama's national security priorities. He joined Obama's Senate staff in 2005 and then served a tour as an intelligence officer for Navy Special Forces in Iraq. He has told friends that he has long felt the call of duty to return to the SEALs, but that he wanted to make sure the NSC staff was on a firm footing before he left the president's service. A White House official said that Lippert had discussed his desire with Obama before he joined the administration. The same official said that Lippert hoped to return to the White House after his tour was up.

Replacing Lippert will be Denis McDonough, Obama's second-longest-serving foreign policy aide and a constant voice in Obama's ear. Ben Rhodes, Obama's top foreign policy speechwriter, has been promoted to McDonough's old job -- Deputy National Security Adviser for Strategic Communications.   Both Rhodes and McDonough are as responsible for the development of his foreign and national security policies as almost any other advisers; they've got an ear for Obama's words and generally get the narrative that Obama is trying to write. (The "writing a narrative" idiom is something Obama likes to say in private when discussing foreign policy communication.)

Is there any palace intrigue to Lippert's departure? Nothing significant. His relationship with his immediate boss, the National Security Adviser, Gen. James Jones, though not without its tensions, but was general friendly.  Lippert developed a rapport with Jones during the presidential campaign, when Jones would use Lippert to pass thoughts and suggestions to candidate Obama.  There has been some  grumbling, largely unspecific, about the policy process that, under Jones's guidance, Lippert put into place. Lippert is used to military discipline; many NSC and administration civilians are not.

Other critics of Lippert's envied the open-door access to the president he possessed and blamed him for blocking deputy-level political appointees that he did not believe would be good fits for his boss.  The extent to which Lippert influences Obama's hiring decisions is overstated, but Lippert's general level influence -- particularly over Obama's Iraq and Afghanistan policies and his advice to Obama about the way to deal with generals and the civillian bureaucracy at the Pentagon -- was high.

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