Journalist Glenn Greenwald slammed President-elect Joe Biden’s pick for defense secretary as “yet another high-level Biden nominee enmeshed in D.C.'s corporatist ‘revolving door’ of legalized influence-peddling.”

Biden on Monday named retired Army Gen. Lloyd Austin, who serves on the board of Raytheon Technologies, to serve as the Pentagon chief. 

“If confirmed, Raytheon will have a very good friend in charge of the bloated $750 billion annual U.S. defense budget,” Greenwald wrote on Twitter. 

Biden’s long-standing relationship with Austin was a key factor in his selection, a source with knowledge of the matter told Fox News’ Peter Doocy. Austin served as commander of U.S. and Coalition forces in Iraq during former President Barack Obama’s first term in office.

BIDEN TO NOMINATE RETIRED FOUR-STAR ARMY GENERAL LLOYD AUSTIN FOR DEFENSE SECRETARY 

Austin was tapped for the secretary of defense role over Michele Flournoy, a former senior Pentagon official who had been considered a frontrunner for the position.

As a career military officer, Austin was sure to face some pushback from those who believe in drawing a clear line between civilian and military leadership of the Pentagon. 

Although many previous defense secretaries have served briefly in the military, only two — George C. Marshall and James Mattis — have been career officers. Marshall also served as secretary of state.

Like Mattis, Austin would need to obtain a congressional waiver to serve as defense secretary, due to a law that renders ineligible anyone who’s served as an officer in the armed services within the last seven years.” Austin retired in 2016. 

A key House Democrat has pushed back on Austin’s appointment -- Rep. Elissa Slotkin. 

Slotkin, a former CIA intelligence analyst who served in the war in Iraq three times under then-Presidents Barack Obama and George W. Bush, says that choosing retired Austin to lead the Defense Department, a position traditionally reserved for civilians, “just feels off.”

“I have deep respect for General Lloyd Austin. We worked together on Iraq when he commanded U.S. forces there, when he was vice chief of the Army, and when was the CENTCOM commander,” the moderate Democrat from Michigan wrote in a statement.

“But choosing another recently retired general to serve in a role that is designated for a civilian just feels off. The job of secretary of defense is purpose-built to ensure civilian oversight of the military,” she emphasized.

“After the last four years, civil-military relations at the Pentagon definitely need to be rebalanced. General Austin has had an incredible career — but I’ll need to understand what he and the Biden Administration plan to do to address these concerns before I can vote for his waiver,” Slotkin emphasized.

KEY HOUSE DEMOCRAT PUSHES BACK ON BIDEN PICKING GENERAL FOR DEFENSE SECRETARY 

Trump named a high number of retired generals to top civilian posts in his administration. Among them were retired Marine Corps Gen. John Kelly as homeland security secretary and later White House chief of staff, and retired Army Lt. Gen. H.R. McMaster as national security adviser. The president, while highlighting his efforts to rebuild the military during his tenure, has also been targeted by critics for politicizing the military.

Greenwald pointed out that after Trump’s “militarization” of the government, Democrats added to their 2020 platform called to restore “healthy civil-military relations.”

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“Democrats believe that healthy civil-military relations are essential to our democracy and to the strength and effectiveness of our military,” the platform read. “We will end the Trump Administration’s politicization of the armed forces and distortion of civilian and military roles in decision-making.”

Fox News' Thomas Barrabi and Paul Steinhauser contributed to this report.