The nomination of former Obama National Security official Colin Kahl for a top position in the Biden Pentagon may have hit another snag, as Sen. Bill Hagerty (R-TN) expressed concern that Kahl may have leaked classified information on Twitter.

President Joe Biden has nominated Kahl, who served as Biden’s National Security Adviser during the Obama administration, to serve as undersecretary of defense for policy, the number three job at the Pentagon.

However, a number of Republican senators have expressed reservations about his judgment and highly partisan tweets, and on Friday, Sen. Bill Hagerty (R-TN), who served as U.S. ambassador to Japan during the Trump administration, released a letter to the leaders of the Senate Armed Services Committee (SASC) expressing concern that some of Kahl’s tweets after leaving the Obama National Security Council contained leaked information from colleagues who still worked there.

Typically, the National Security Council is staffed not with political appointees, but with career officials designated from agencies such as the State Department, Defense Department, and others. Therefore, it is common for NSC officials to remain in their jobs even with a change in the administration.

Hagerty wrote to SASC chairman Jack Reed (D-RI) and ranking member Jim Inhofe (R-OK): “I am concerned that Kahl, in his capacity as a private citizen shortly after leaving senior government service, may have been knowingly leaking, or otherwise disclosing on Twitter, sensitive information, including classified information.”

Hagerty explained:

The substance, meeting agendas, and schedules of the National Security Council (NSC), NSC Principals Committee, and NSC Deputies Committee are typically considered to be so sensitive that the NSC Executive Secretary classifies them, distributes them by courier or via classified network to only a limited group of interagency offices, and classifies the summaries of meeting proceedings. Some of the information that Kahl appears to have publicly disclosed is of a category to which even Senators and Senate staff with the highest security clearances are almost always denied.

Hagerty described various examples of Kahl tweeting such information, including on March 1, 2017, when he tweeted, “I heard [the] Yemen portion of 1/26 Deputies mtg (held AFTER Trump approved raid) lasted < 30 min, ending w/[Deputy National Security Advisor] KT McFarland saying ‘saddle up’.”

Kahl tweeted the next day, “I have confirmed with 4 separate staffers in the room.”

He tweeted in late January and early February 2017 that he was “hearing” information concerning how then-President Donald Trump was receiving his classified President’s Daily Brief.

“Kahl was effectively revealing to America’s adversaries details of Presidential decision-making and prioritization in national security affairs. This is knowledge of a kind that foreign intelligence services likely expend great resources to acquire, including through espionage,” Hagerty wrote.

“If Kahl disclosed this national security information as it appears he did, he would have been exhibiting either politically-driven and reckless disregard for security protocols or, at a minimum, serious negligence,” he added.

He urged Reed and Inhofe to ask him about these disclosures before a full vote in front of the Senate to confirm him.

So far, SASC, which must approve him for a full Senate vote, has not yet confirmed him, and that vote remains delayed.

In 2019, Kahl once tweeted that the Republican Party is the “party of ethnic cleansing.”

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