Mark Esper checks out a helicopter cockpit during a visit to Fort Knox, Ky.

WASHINGTON: The Pentagon saw its third Acting Defense Secretary take the job within the span of a month on Monday at 3:04 p.m. when the White House formally nominated Mark Esper. The formal nod came less than a day before Esper was scheduled to appear before the Senate Armed Services Committee for his nomination hearing.

The move sets off a complicated chain of events that underscores the uncertainty that has plagued the Trump administration’s foreign policy as a carousel of officials are hired, fired and leave — often with no replacement lined up beforehand.

With the Senate’s receipt of the Esper nomination, Navy Secretary Richard Spencer officially became the latest Acting Defense Secretary, while Comptroller David Norquist stays in place performing the duties of the Deputy Defense Secretary. Now that Spencer has left the Navy’s helm, his undersecretary, Thomas Modly, takes over as secretary. The only person currently occupying the job he was nominated for, Undersecretary of the Army Ryan McCarthy, steps down from his temporary post as Secretary of the Army to head back to his old job.

“Secretary Spencer has the full authority and responsibility of the Secretary of Defense,” Jonathan Hoffman, chief Pentagon spokesperson, said in a statement. “The senior team supporting the Office of the Secretary remains in place to ensure institutional continuity.” 

Esper took over from Patrick Shanahan last month after Shanahan resigned after messy details of his family life became public.

At the time, Shanahan had been the longest-serving acting defense secretary in history, a record Esper is unlikely to match. (The fact that record was set is itself an indicator of the depth of turmoil in the administration’s national security ranks.) Both Republican and Democratic members of the Senate Armed Services Committee, tired of months of acting officials leading the Pentagon, have indicated they want Esper to be seated quickly. 

The only wrinkle that has presented itself so far is Esper’s previous work as a Raytheon executive who led the company’s lobbying efforts from 2010 to 2017. The Hill newspaper recognized Esper as one of Washington’s top corporate lobbyists in 2015 and 2016.

Esper has already survived the nomination process to become the Army’s top civilian, but will be required to recuse himself from any decisions having to do with the giant defense contractor who once signed his checks.

After meeting with Esper last week, Sen. Elizabeth Warren, who is running for president, sent his office a letter saying she is “concerned by the cozy relationship between giant defense contractors, the DoD, and the White House.” This is a clear echo of concerns earlier expressed by Warren and the late Sen. John McCain when Esper was nominated for his Army post.

Esper’s 2017 ethics agreement, which mandates he recuse himself from any decisions regarding Raytheon, expires in November. In his conversation with Warren, by her account, he refused to commit to extend the agreement. “I am troubled by your unwillingness to fully address your real and perceived conflicts of interest,” she wrote, “and write to ask that you reconsider your refusal to extend your Raytheon recusal through the duration of your tenure at DoD.”

The Trump administration’s nominee to be the next Chairman of the Joint Chiefs, Gen. Mark Milley, cruised through an uneventful nomination hearing last week, and there is little indication that Esper will have a hard time before the Senate Armed Services Committee.