WASHINGTON ― Lawmakers on both sides of nuclear weapons issues want answers after the lead Pentagon official overseeing the Nuclear Posture Review was ousted after nine months on the job and her position eliminated.

The Pentagon is saying the departure of Leonor Tomero, the former deputy assistant secretary of defense for nuclear and missile defense policy, was due to a reorganization. However, non-proliferation advocates are questioning whether it was because Tomero was an advocate for nuclear restraint, and worry it could bias the review away from President Joe Biden’s pursuit of arms control.

“Congress needs to understand whether ideology played any role in Ms. Tomero’s dismissal,” Sen. Ed Markey, D-Mass., a proponent of nuclear arms control and nonproliferation, wrote in a Sept. 24 letter to Biden that included nearly a dozen questions.

“I am also concerned that the sudden departure of a top appointee, charged with presenting you options on the future of the U.S. nuclear weapons enterprise, will result in a draft Nuclear Posture Review that reflects the Cold War era’s overreliance on nuclear weapons, rather than your lifetime of work championing policies that reduce nuclear weapons risks,” the senator added.

Politico broke the news last week that Tomero, who was leading reviews of nuclear weapons and missile defense policy, was leaving and that her responsibilities would be absorbed by the Pentagon’s new assistant secretary for space. Tomero’s former boss, Melissa Dalton, who is performing the duties of assistant secretary of defense for strategy, plans and capabilities, will lead the Nuclear Posture Review in Tomero’s place, Politico reported.

The deputy assistant secretary of defense for countering weapons of mass destruction, Richard Johnson, will soon assume the duties of the nuclear deterrence portfolio, in addition to his current role, Pentagon spokesman John Kirby said in a statement Monday. Kirby praised Tomero and seemed to suggest that her work with the Biden administration was not over.

“We are confident she will continue to contribute to U.S. national security in the administration, and we remain grateful for her service,” Kirby said.

The Nuclear Posture Review, due in early 2022, is expected to chart a definitive course for Biden amid competing pressures.

While on the campaign trail, Biden expressed a desire to reduce the role of nuclear weapons in U.S. strategy, and his website says their “sole purpose” is to deter and, if needed, retaliate against a nuclear attack. But there are heated divisions in Congress over the best response to Russian and Chinese nuclear behavior as well as the growing cost of the U.S. nuclear modernization program.

There are two camps within the Biden administration, according to a former defense official. One is focused on arms control, is skeptical of multibillion-dollar nuclear modernization plans and is mainly centered in the State Department. The other is focused on competition with Russia and China, and is deeply concerned that allies under America’s nuclear umbrella would feel abandoned if the country reduced its arsenal.

For more than a decade, Tomero was the House Armed Services Committee’s Democratic professional staff lead for nuclear deterrence, nuclear weapons, nonproliferation, military space and missile defense. There, she worked for now-Chairman Adam Smith, D-Wash., who’s voiced skepticism about the cost of land-based intercontinental ballistic missiles and modernizing them ― and called for the U.S. to adopt a “no-first-use” nuclear weapons policy.

Both sides of the argument have been jockeying amid some apparent contradictions from the Biden administration. While Biden’s first Interim National Security Strategic Guidance stated that “we will endeavor to head off costly arms races and re-establish our credibility as a leader in arms control,” his budget request upset nonproliferation advocates by continuing expansive nuclear weapons sustainment and modernization efforts inherited from the Trump administration.

Tom Collina of the Ploughshares Fund, which advocates for the elimination of nuclear weapons, said removing Tomero — and thus excluding her views that challenged the status quo on nuclear arms — is a disservice to Biden and his pursuit of options for nuclear restraint.

“The reality now is that the person who is going to be drafting the NPR is much more conservative than the person who was going to be doing it,” Collina said. “And what that means is the NPR will not be considering the kind of options President Biden would want to see but that would be threatening to old ways of thinking at the Pentagon.”

What drove the departure wasn’t immediately clear, even to some hawkish lawmakers, including Senate Armed Services Committee ranking member Sen. Jim Inhofe, R-Okla. Amid the expectation that the NPR will coincide with the release of Biden’s fiscal 2023 budget request, Inhofe wanted to hear more from the Pentagon about the matter and is most concerned about prioritizing nuclear issues and preventing hiccups in the review process.

“I was shocked that she was among the first victims of this reorganization,” House Armed Services strategic forces subcommittee Chairman Jim Cooper, D-Tenn., said in a brief hallway interview on Wednesday. “I look forward to finding out what was intended by the reorganization. I just don’t have enough information to know.”

In his letter to Biden, Markey asked why Tomero, given her expertise, wasn’t offered a new assignment in the Pentagon’s reorganized space policy shop.

Markey also wanted to know whether Dalton, Pentagon policy chief Colin Kahl or another official communicated to Tomero the reasons for her dismissal.

Pentagon officials have cast the move as routine.

“It’s natural with any new administration — this one’s not excepted — that we would want to reevaluate the organizational structure and make changes where we think is appropriate to support the secretary’s priorities. And I think, again, without speaking to individuals, we’re certainly doing that,” Kirby told reporters last week. “We’re going to continue to consider and include a wide range of viewpoints in the Nuclear Posture Review, including those from administration officials, military leaders, academics and all others.”

But to Markey, Kirby’s answer was fuel for more questions.

“Please identify the individuals and organizations consulting on the Nuclear Posture Review, including paid contractors,” Markey said in his letter to Biden. “How will the [Defense] Department ensure that the advice of individuals who do not support the default military reliance on nuclear weapons is included in this process?”

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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