WASHINGTON ― President Joe Biden will announce White House national security official Sasha Baker as his pick for deputy undersecretary of defense for policy, Defense News has learned.

Baker, the National Security Council’s senior director for strategic planning, previously served as an adviser to progressive Sen. Elizabeth Warren, D-Mass., and the lawmaker’s 2020 presidential campaign. Progressives on Tuesday hailed the expected move, describing Baker as a leading progressive national security thinker.

During the Obama administration, Baker served as deputy chief of staff to Defense Secretary Ash Carter, who spoke of her in glowing terms.

“Sasha was involved in every single important deliberation in the secretary’s office, so all of our counterterror operations, cyber operations, the entire counter-[Islamic State] campaign,” Carter told Defense News. “She was critical to all our outreach to the tech sector.”

Before the Biden and Trump administration’s focus on bringing forward-leaning technologies to the Pentagon, Carter established the Defense Innovation Board. He credited Baker with bringing in the board’s first chairman, former Google chief executive Eric Schmidt, as well as other tech “superstars.”

The Pentagon’s policy shop is expected to play a key role as the Biden administration grapples with a deteriorating Afghanistan and shifting force posture in the Middle East. Baker, who was involved in drafting the Biden administration’s first national defense policy document, would also have a lead role implementing it, if confirmed.

“She was very involved in everything we did in Afghanistan, Iraq and Syria ― and the force structure and operational decisions ... so she knows very well all the issues involved in positioning forces in that theater, and that’s an important priority,” Carter said.

Baker rose from House staffer to budget analyst in the Office of Management and Budget’s homeland and national security divisions during the Obama administration. She was credited with later shaping Warren’s national security agenda, which took aim at rising defense budgets and the revolving door between the Pentagon and the defense industry.

When Baker was tapped for the National Security Council in January, Warren endorsed Baker as an “excellent choice.”

“Sasha Baker has been by my side in Iraq, Afghanistan, China, and the DMZ. She understands that our national security can’t solely be run by the Pentagon for the wealthy and well-connected,” Warren said, using an abbreviation for the Korean Peninsula’s Demilitarized Zone.

The nomination comes after Biden’s pick for defense policy chief saw some of the toughest scrutiny of any of his national security nominees so far. In April, the Senate confirmed Colin Kahl to be the undersecretary of defense for policy despite unified opposition from Senate Republicans who took issue with his history of tweets attacking Republican lawmakers and support for the controversial Iran nuclear deal.

Baker is the third senior director in this administration’s National Security Council to be nominated for a major position. Biden has nominated Mallory Stewart for a State Department arms control post and Barbara Leaf to be assistant secretary of state for near-eastern affairs.

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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