done.”

The chief of staff also acts as a “gatekeeper,” managing whom the president communicates with — and whom he doesn’t.

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“It’s easy if you’re in charge of anything to just get consumed with answering the phone call or answering every email where everybody wants to talk to you … And none of the time doing what you’ve been hired to do, which in this case is run the country,” Loge said.

Loge said Zients was chosen because of Biden’s trust in him and his background in managing large, complicated organizations. He also brings experience from the Obama administration, when the president faced a hostile Republican Congress — something Biden will now have to contend with, beginning with a possible debt-ceiling showdown.

That specific conflict “is not something that a lot of people have done before because mercifully, it’s not something that happens very often. So he goes in with a bit of experience.”

Andy Slavitt, a former senior adviser for pandemic response to Biden, told the NewsHour that Zeints “is focused on execution, the unsexy stuff of getting decisions made in government.”

Slavitt worked with Zients in both the Biden and Obama administrations, including work on fixing the Affordable Care Act website in 2013.

“There were times when we were working on the ACA fix together, when we would talk every two hours, including in the middle of the night,” said Slavitt.

“He would basically, metaphorically, climb in the foxhole with you say, ‘O.K., what do we need to do?’”

Loge believes that criticisms of Zients from groups like the Revolving Door Project miss the mark.

“His job is not to set policy or policy direction. His job is not to say who should get how much money or what laws should be implemented. His job is to make the machine work,” Loge said.

Loge noted that serving as a gatekeeper may give the chief of staff some ability to control whose viewpoints the president hears. But he also doubted that Biden would be likely to change his views much after 50 years in national politics.

“Biden knows what Biden’s gonna do, right?” Loge said. “Biden served in the U.S. Senate for a long, long time. He was vice president of the United States for eight years. He’s been president of the United States for two years. There isn’t an issue that he doesn’t have an opinion on.”

Laura Barrón-López and Geoff Bennett contributed reporting.