President Obama's deputy national security adviser has gone on leave in order to return to active duty in the U.S. Navy, the White House announced today.
Mark Lippert, who serves as deputy national security director and National Security Council chief of staff, is passionate about the Navy, Mr. Obama said in a statement today, so his decision was not a surprise.
The president said Lippert will always have a senior foreign policy position in this White House, when he chooses to return to civilian life.
"I will miss Mark and his counsel, his excellent work at the NSC, and his good cheer," the president said. "I support his decision. He is a close friend, and I admire and respect his devotion to our country and answering the call to active duty service."
Lippert, 36, is Mr. Obama's longest-serving foreign policy adviser, according to The Atlantic's Marc Ambinder, who is also CBS News' chief political consultant. He joined Mr. Obama's Senate staff in 2005 and then served a tour as an intelligence officer for Navy Special Forces in Iraq.
"He has presided over an intricate and occasionally thorny reconfiguration of the 200 person NSC staff to better reflect Obama's national security priorities," Ambinder writes. "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."