Karen Bass was elected mayor of Los Angeles in 2022 on a pledge to reduce homelessness, drawing on her decades of experience in government. She won decisively and proceeded, with some success, to begin moving people off the streets and into shelter.

But the fire that destroyed much of the Pacific Palisades this month has rewritten the job description. If Ms. Bass was hired to be the pragmatic city manager with a command of government, Los Angeles is now looking for a general in a hard hat.

Her style — reserved and conciliatory, marked by the circumspect language of someone who once was the leader of the California State Assembly — was on display last week during a tense meeting in the Palisades with President Trump.

The Republican president talked over her, often to applause from homeowners, and told the mayor that she should let residents of Pacific Palisades, which is part of the city of Los Angeles, begin clearing their properties “tonight.” Ms. Bass, a Democrat, responded with talk about process and regulations, explaining that she had waived city rules but that clearing contaminants would take time so that the Environmental Protection Agency could ensure the safety of residents.

It was not what homeowners wanted to hear.

“It feels like she’s not in the room,” said Emily Bianchi, a self-described progressive whose Pacific Palisades home was destroyed in the fire and who attended the panel with Mr. Trump and Ms. Bass. “And, oh my God, he is in the room and he fills it up. She just took a back seat.”

The encounter between Mr. Trump and Ms. Bass captured in many ways why Ms. Bass has by all appearances struggled to win the confidence of residents after one of the largest American catastrophes in recent decades.

It also displayed the sharp differences between the newly inaugurated president and the Democratic Party itself. Mr. Trump is a New York developer who has often steamrolled the rules and complained about regulations while Democrats like Ms. Bass have spent their lives working in government because they viewed it as a solution rather than a hindrance.

“She’s careful not to offend,” said Matt Bennett, the founder of Third Way, a Democratic think tank based in Washington. “She stays within the lines, does not violate norms.”

But during these difficult days, with the flames barely extinguished, Ms. Bass’s deliberate nature has fed the frustration among many constituents, despite some progress she has made over these past two years in dealing with homelessness, the issue that was so central to her election.

“She is a trained social worker, trained community activist — what better credentials for dealing with homelessness?” said Fernando Guerra, the head of the Center for the Study of Los Angeles at Loyola Marymount University. “But in 2025, that is not the No. 1 issue.”

A few days after her session with Mr. Trump, Ms. Bass sought to display her empathy as she walked through the commercial district of the Palisades, trailed by homeowners, television cameras and aides. She paused in front the blackened frame of what had once been a Ralphs supermarket.

“The grief and the pain, the denial and the anger that everyone feels is so palpable,” Ms. Bass said. She talked about the challenges of rebuilding and tried to assure residents that this part of Los Angeles would retain its character, as an upper-middle-class neighborhood with mostly single-family homes, set between the hills and the ocean.

She then lapsed into talk of process and procedure.

“Make sure you’re only here for a short period of time, and that’s mainly for health reasons,” she said. “The first phase is going to begin when the E.P.A. comes in, and in a few days, the county will have a form ready — the right to entry form. Then the second phase, when the debris removal happens, people can go ahead and fill out that form and we’ll give you more information about that.”

In the long run, Ms. Bass’s focus on compromise and conciliation — the skills that helped her become a successful Assembly speaker — may well prove valuable in the complex negotiations over rebuilding that Los Angeles faces in the years ahead.

Ms. Bass became mayor after serving as a member of the California State Assembly before rising to become its speaker. She served for 11 years in Congress before she was elected mayor.

Mr. Trump, by contrast, has run for only one office in his life — president.

“She comes from a place where you build teams and work together,” said Steven Maviglio, who served as deputy chief of staff for Ms. Bass in the Assembly. “He comes from a place where he yells at people and tell them what to do.”

Mr. Trump was in Los Angeles for about four hours last week, while it will be Ms. Bass’s job to navigate the complicated network of governments in Los Angeles for months to come. (Ms. Bass is not directly responsible for the Eaton fire recovery in Altadena, which is part of Los Angeles County but not the city. She has nonetheless drawn criticism from residents there as well.)

Ms. Bass is the chief executive in a city of nearly four million people where the council has most of the power. Many of the levers of cleanup and recovery are held by other levels of government, like the county and federal agencies. The man she defeated for the mayoralty — Rick Caruso — is a developer from the Palisades, who has a keen understanding of the issues the city is likely to confront now. And he is also considering running against her again.

Ms. Bass, 71, made it clear that she did not view the mayor’s office as a steppingstone when she ran in 2022. She was coming home from Congress to do one more stint for the city in which she grew up. The mayor was not available for an interview.

As a rule, people turn to elected officials — mayors, governors, presidents — for comfort and leadership during crises. Ms. Bass’s predecessor, Eric M. Garcetti, led regular televised briefings for residents during the Covid pandemic.

But Ms. Bass has had difficulty breaking through. She came under immediate criticism for being away from Los Angeles for a diplomatic trip in Ghana when the fires broke out, leaving emergency officials and other local leaders to stand in for her during news conferences in the first 24 hours. The absence lingered in the minds of some residents.

At subsequent news briefings, she often found herself as one in a long line of elected officials and Fire Department leaders giving updates. The other day, she stood with public officials and firefighters behind Gov. Gavin Newsom of California as he signed an emergency $2.5 billion wildfire relief bill in Pasadena, which is outside the city of Los Angeles. She did not speak.

“People want somebody who can snap their fingers and can get things done,” Mr. Maviglio said. “She’s got to prove that she can do that.”

The question in the months ahead is whether the mayor Los Angeles has seen for these past two weeks may prove more suited to the behind-the-scenes negotiating ahead.

“What’s going to matter is the work of rebuilding,” said Darrell Steinberg, who served as leader of the California State Senate when Ms. Bass was Assembly speaker and who went on to serve as mayor of Sacramento. “She is perfectly suited for that world. It’s going to require an enormous amount of collaboration and organizing.”