Two months before he was pushed out as defense secretary, Chuck Hagel penned a private letter to the White House, arguing for new measures to rein in Russian President Vladimir Putin and greater efforts to reassure anxious European allies, according to officials briefed on the matter.
Shortly after the September letter, he wrote another memo calling for the administration to clarify its approach to the conflict in Syria. The two messages capped a year of frustrations for Mr. Hagel, who repeatedly found fault with what he saw as indecisiveness by the White House National Security Council, according to current and former officials close to him.
"One of the things that Hagel values most is clarity," said a confidante of the defense secretary. "That's not something that this White House has always done well."
Mr. Hagel's frustrations grew in 2014.
Mr. Hagel wasn't alone in his frustration. His upset over what he saw as slow decision-making and White House micromanagement of the Defense Department was shared by his two immediate predecessors at the Pentagon.
The danger, Mr. Hagel told aides, was that Mr. Putin would interpret U.S. inaction as indifference, and conclude he can do to Ukraine whatever he pleases. Moreover, he thought over-promising and under-delivering would undercut U.S. credibility.
Mr. Hagel tried to move the ball forward with Mr. Obama directly. In a private meeting in late July, he warned Mr. Obama that the U.S. wasn't focused enough on Russia, and was lurching from crisis to crisis without direction, according to a senior defense official.
Moscow - not the Middle East - posed the most serious long-term threat to international security, Mr. Hagel told the president. He said the US needed to find a way to de-escalate tensions with Russia and counter either the impression or reality of Russia and China moving more closely together.
Mr. Hagel followed up with the September letter, warning the White House that decisions may need to be taken soon on what officials called "creative" new options to rein in Mr. Putin before the situation escalates.