The Pentagon's top policy official was out of a job Wednesday in the continuing fallout from the holdup of military aid to Ukraine and the ensuing impeachment process.
In his letter of resignation, Rood said he had learned from Defense Secretary Mark Esper that President Donald Trump wanted him out. "As you have requested, I am providing my resignation effective February 28," Rood said in the letter to Trump.
In response, Trump sent out a tweet thanking Rood for his service and wishing him "well in his future endeavors," but he also shared a Bloomberg news report suggesting that Rood was not on board with the administration's policies.
The report said that Rood "faced pressure to resign from some who lost confidence in his ability to carry out Trump's agenda."
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At a news conference, Jonathan Hoffman, the Pentagon's chief spokesman, said he was "not going to speculate on the motivations" behind Rood's apparent firing, but noted that it is the "president's prerogative" on whether a political appointee should be retained.
"The president can make a decision to go in a different direction," he said.
Hoffman would not confirm that Esper had asked Rood to step down, saying he had not put the question to the SecDef.
In a statement, Esper said Rood had "played a critical role on a wide range of DoD issues including modernizing our nuclear deterrence capability, efforts to increase burden sharing by our NATO allies, our Missile Defense Review and implementing the National Defense Strategy. I wish him all the best in his future endeavors."
Hoffman said that Dr. James Anderson, the current senior official performing the duties of the deputy under secretary of defense for policy, would take on Rood's job until Trump picks a replacement, subject to Senate confirmation.
Rood, whose resignation was first reported by CNN, certified last July that Ukraine had met the requirements to receive $250 million in military aid at the same time that the Trump administration was withholding that aid.
Rood's certification appeared to undermine the argument made by Trump's defenders in the impeachment process: that the aid was withheld because of the president's concerns about corruption in Ukraine.
Since his acquittal by the Senate, Trump has moved quickly against those he believes testified unfairly against him in the impeachment process.
Army Lt. Col. Alexander Vindman, a Ukraine and Russia expert on the White House National Security Council staff, was marched out of the White House by the Secret Service. European Union Ambassador Gordon Sondland resigned after being recalled from his post.
Vindman's twin brother, Army Lt. Col. Yevgeny Vindman, a lawyer on the National Security Council, also was ordered to leave.
Rood came to the Defense Department with a wide range of government, Capitol Hill and private-sector experience.
He held positions at the State Department, the White House National Security Council and the CIA, and also worked as an adviser to former Republican Senator Jon Kyl of Arizona. In the private sector, Rood worked for major defense contractors Lockheed Martin and Raytheon.
-- Richard Sisk can be reached at Richard.Sisk@Military.com.
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