Austin's selection, like many of Biden's top picks, appears to have been based heavily on his deep personal connection with the president-elect.

Then-Vice President Biden got to know Austin during the Obama administration when he was leading Iraq policy and Austin was a commander in the Middle East. The two spent “countless hours” together, in the field and in the White House Situation Room, Biden wrote in a Tuesday piece for the Atlantic explaining his decision.

Austin also developed a close relationship with Biden’s late son, Beau, when he served on Austin’s staff in Iraq in 2008 and 2009, said one source close to the discussions, who asked not to be named to discuss private matters. Austin and the younger Biden attended Mass together, sitting side-by-side almost every Sunday, and they kept in touch after Beau returned from his deployment.

“The fact is, Austin’s many strengths and his intimate knowledge of the Department of Defense and our government are uniquely matched to the challenges and crises we face,” Biden wrote. “He is the person we need in this moment.”

Biden also hailed Austin’s critical role in “the largest logistical operation undertaken by the Army in six decades,” the Iraq drawdown — an experience that will serve him well as Defense secretary overseeing the military’s distribution of Covid-19 vaccines.

But a host of new questions emerged on Tuesday about Austin’s 41-year record in the Army and the qualifications he would bring to a much more expansive portfolio as the top civilian overseeing the Department of Defense.

In particular, national security experts raised concerns about Austin’s lack of experience handling what many consider to be the most pressing challenge facing the United States for years to come: an increasingly aggressive China.

“This suggests quite loudly to me that Biden doesn’t take hard power, and the China military threat as seriously and urgently as we need to,” said Elbridge Colby, a former defense official and a lead author the 2018 National Defense Strategy that laid out the Pentagon’s pivot from counterterrorism to great power competition.

Despite making strides to address the Chinese threat during the Trump administration, the U.S. military continues to be surprised by the pace and sophistication of Beijing’s military buildup, Colby noted. In some ways the U.S. is already falling behind, he added.

“Lloyd Austin has an extremely distinguished military career — but to me that’s not really the issue. What we need is someone who already is at the forefront of thinking and leadership on Asia and China, on aerospace and maritime power, and on technology," Colby said. "That's what not Austin's background brings to the table, and we’re way beyond the point where we can have someone who doesn't have that.”

Bilal Saab, another former Trump-era defense official and Middle East Institute expert, also raised questions about the gap in Austin’s background.

“I am wondering how his lack of policy experience will influence his ability to translate the president's political priorities," he said. "I am concerned about his lack of Indo-Pacific background, which is our new foreign policy priority."

Austin himself has indicated that he sees great power competition as the primary national security and foreign policy challenge.

“We’re seeing shifts in the character of global competition between the U.S. and our competitors,” he told students at the Army’s Command and General Staff College in 2018. “While we continue to be the world’s sole superpower, our adversaries are pushing back. They are building capabilities. They are narrowing the gap between us and them, both in terms of technology and combat experience. And this especially holds true for nation states such as Russia and China.”

“For example,” he added, “Russia’s involvement in Syria. They like to say publicly that they’ve been helping us to fight the bad guys, the Islamic State. But the truth of the matter is they were, and are, the bad guys.”

Austin’s confirmation hearing before the Senate Armed Services Committee is likely to focus on his oversight of the wars in the Middle East as the head of U.S. Central Command from 2013 to 2016. His advice about how many troops Biden should keep in Iraq, Afghanistan, Syria and other conflict zones in the region are likely to be of paramount interest amid President Donald Trump's 11th-hour troop withdrawals.

Biden praised Austin's oversight of Central Command, noting that when the Islamic State emerged as a terrorist threat in Iraq and Syria, he and Obama leaned heavily on Austin, who "designed and executed the campaign that ultimately beat back" the terrorist group.

But many military officials see his last command as a spotty period in his career, which included stints at the top officer in Iraq and the vice chief of staff of the Army.

Austin faced particularly tough questions in 2015 about the U.S. military’s role training forces in Syria to fight the Islamic State in Iraq and Syria during the country’s civil war, acknowledging that the U.S. spent some $500 million but trained only a handful of fighters.

The late Sen. John McCain interrogated Austin about the U.S. military’s fight against ISIS in a memorable 2015 hearing that at some points left the general at a loss for words.

“I must say, I've been a member of this committee for nearly 30 years, and I have never heard testimony like this, never,” McCain said.

Austin's appearance before the committee on Syria "was one of the most awkward I ever witnessed," one former Senate Armed Services Committee aide to McCain told POLITICO. While McCain held Austin in high esteem, the senator was "clearly frustrated with and disappointed in his leadership at CENTCOM," the aide said, adding that other lawmakers felt the same.

"It was a sad encapsulation of an incoherent Syria policy marred by a long string of military failures made uncomfortable by General Austin’s apparent inability to confront the reality of the situation and present a compelling way forward," the former aide said.

Another cloud hanging over the command at the time was allegations that Central Command downplayed intelligence reports on the threat posed by the terrorist group and painted a brighter picture of the progress of U.S. military efforts.

Austin’s command was cleared in an investigation by the Defense Department’s inspector general in 2017.

But it was Austin’s early view on the terrorist group that took over large swaths of Iraq and Syria that led President Barack Obama to regretfully label ISIS the “jayvee team," one report said.

Austin told Obama in 2015 that the group was a “flash in the pan,” according to allegations published in The Atlantic magazine in 2016. A spokesperson for Austin denied he ever said that.

What the general has been up to the last four years is also very much on the minds of progressive groups and government watchdogs who have concerns about his corporate ties.

After he retired, Austin joined the board of directors of Raytheon Technologies, one of the largest Pentagon contractors. He is also on the board of Nucor, the largest American steel producer, as well as health care company Tenet.

Public records show that he runs his own consulting firm, Austin Strategy Group, LLC, located in Great Falls, Va., but the firm has little public presence and its client list is not publicly available.

He is also a trustee of the Carnegie Corporation of New York, a philanthropic foundation.

John Warner, the former Republican chair of the Armed Services Committee, said on Tuesday that one consequence of appointing a retired general is that his career is relatively easy to assess. “It’s an open book. It’s basically public,” he said of Austin’s military record.

But Warner said in an interview that he would like to know more about Austin's activities since leaving the military.

“Men who have worked their way up the ranks like that have had to really ingratiate themselves,” Warner, who also served as secretary of the Navy, said. “You’ve got to be careful of the old axiom ‘you scratch my back and I’ll scratch yours’. That goes for [their relationships with] civilians and often defense companies.”

The bigger questions are likely to center on his approach to the nearly countless issues that will be his responsibility if he becomes secretary of Defense.

Saab, for example, said he wonders about Austin’s ability to handle the large Pentagon bureaucracy after decades in the field.

"Above all else, can he manage a huge bureaucracy such as the Pentagon," he said. "That requires a unique ability and nothing in his background shows that he has that capability.”

And he will have to develop a more sophisticated worldview on longer term challenges to U.S. national security, including nontraditional threats such as climate change and pandemics.

“This guy was a recently retired commander for U.S. Central Command, so very well informed on terrorism and operations in the Middle East,” said Guy Snodgrass, a former Navy officer who served as chief speechwriter for Mattis from 2017 to 2018. “But how will he be able to shift gears into the much more strategic issue of the Indo-Pacific?”

Snodgrass, who is now CEO of Defense Analytics, believes the similarities between Austin and Mattis, who was also a former commander of U.S. Central Command, are cause for concern.

“There was a talent and brain drain that occurred under Mattis because he was such a militaristic leader,” he said. “That I think is going to be a challenge for Austin. Mattis still saw everything through the lens of a combatant commander."

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