Senator Laphonza Butler came to her job in Congress in an unusual way and quickly decided she was not going to stay.

Gov. Gavin Newsom of California appointed Ms. Butler in early October after the death of Senator Dianne Feinstein to serve out the remainder of her term, which ends in 2025. The former Emily’s List president, who once headed California’s largest labor organization, is not a candidate in the crowded Democratic primary for the 2024 nomination to succeed Ms. Feinstein permanently.

Ms. Butler, 44, recently spoke to The New York Times from her Senate office about why she opted not to stay in Congress, where she hopes to focus her attention while she is there and the unlikely areas where she has found commonality with some Republicans.

This interview has been edited and condensed for clarity.

You’ve been in office for about two and a half months now. What do you think?

It has been a big change, a big shift for me to have your life, essentially wholly upset in about 24 hours. It has been a great honor, an incredible responsibility in this moment for our country and for the world. And it has been revelatory in terms of time — how fast it goes and how slow it goes all at the same time.

Pace has been the struggle. I know that my colleagues appreciate the challenges that everyday Americans are dealing with, and I think that there is a sense of urgency to solve challenges that are in front of us. The legislative process is much more structured, much more traditional, much slower than anything that I’ve ever experienced before.

Just over two weeks after you were appointed to be the junior senator from California, you announced that you were not going to run for a full term. Help us understand why not.

It was clear to me that I could raise the money. It was clear to me that with a lot of work, I could earn the vote of Californians. So knowing that I could do it was one question. The subsequent question had to be, did I want to do it? And I think serving in elected office is a role you have to want and you have to want deeply. This was never an opportunity that was on my bingo card, and there is no doubt that I want to continue to serve the people of California to use my voice and skill at its greatest capacity. I just didn’t want to be a U.S. senator.

I knew what I wanted to do was to be a mom to my 9-year-old. What I wanted to do was to continue to be a loud and clear voice on things that I know, communities that I identify with and care about. I say to my daughter all the time, ‘There are no nevers.’ And so I don’t close the door on serving in elected office in the future; I just know that it’s not my opportunity at this moment.

With just over a year left in office, where do you plan to focus?

As I occupy the responsibility of being California’s junior senator, one of the youngest senators in the chamber, one of few school-age parents in the chamber, only our nation’s third Black woman and 12th Black person right now, the greatest thing that I can do is to create space for generations to come.

The work that we have to do has to be about legislating for our country’s future — issues of housing, challenges of mental health and recovery from a global pandemic, the deployment of incredibly powerful artificial intelligence and the utilization of social media. And they have to be thought about in a way that best centers those who are going to live the longest through it.

The voices of young people — millennials, Gen Z and generations that are coming after us — legislating with those lives in mind, I think is one of the greatest uses of my time here in the Senate.

There are a number of things that young voters have said to us that are top of mind and that young workers have said to us that are top of mind. So we have a crisis of mental health for young people where data tells us that more young girls are contemplating suicide, that increasingly young people are experiencing deep isolation post-pandemic. Mental health, and particularly youth mental health, is an issue that I want to dedicate some real time and attention to.

We have to see them as whole people, not just voters when November comes around.

When people think about the Senate, a lot of the conversation has been around how old the Senate is. Do you think it’s going to be a challenge to bring a focus to youth and young people?

Youth issues are American issues. Will it be a challenge? Maybe. It also could be an opportunity. It also could be a way for colleagues to think about how they want to engage young people in their states. It may actually be a place of inspiration.

There’s the saying around here that the people who are closest to the pain have the best solutions. And I think often we forget that even as a young person, a child, they too are close to the pain.

My daughter was here in the Senate yesterday, and it hurt my heart to hear her casually talk about the lockdown that happened at her school. It was as if she was talking about coloring class. She was telling one of the staff here in the Senate office about me going to pick her up during a lockdown. And what I hope that we’re able to do is to center not only my daughter’s story, but the story of America’s children, the pain that they are feeling, and that they quietly and casually express that we as adults in their lives have the responsibility to do something about.

I’m curious what you think the role of Congress is — and whether you think the institution is fulfilling that role.

Um, no. The world is complicated. We are seeing the fragility of our democracy. We are experiencing those who would intend to corrupt the integrity of our institutions, who seek to divide at every opportunity. And I think that Congress is a reflection of that in so many ways.

There are those that I have met who are instruments of that division, who are perpetuators of those things that divide the people of our country. When you have one chamber of Congress who takes three weeks to elect a speaker, who so quickly in their majority, post-’22, advanced three pieces of legislative language and/or resolutions that further take away the right of a woman to make decisions about her own body — but we had just experienced the unity of the heartland of America, in places like Kansas and Ohio, where the American people are clear about who should be making those decisions — it’s clear that Congress as a whole is not representing the complexity of the moment, the voices of the country in this moment.

I’ve talked to a lot of members who are retiring or not seeking re-election. And I’m curious if you think that what you just described plays into those decisions to leave — and did it play into yours?

It might be, if I’m being honest with you. I have seen so much happen across the country, in communities and cities and counties and states where the decisions of Washington actually go to get implemented. It starts with, what is this body able to accomplish? Those states and counties and cities don’t have the resources or the policy frameworks to really drive or execute their work without members in the Senate and in the House. And so they are not disconnected for me. We need committed advocates, leaders who are also doing the work outside of government to be able to make our democracy truly vibrant and push it forward in a way that advances everyone.

Do you talk to your colleagues about that frustration?

I think there’s real knowledge about how frustrated the American people are. It then becomes about how do you listen for what’s being said? There are lots of places of commonality. You might not think that California and Alabama have anything to do with each other. But in my conversations, getting to know Senator [Katie] Britt [a Republican] from Alabama, who also has school-age children, I learned Alabama is 47th in the nation when it comes to mental health access. And you compare that with the L.A. Times story that we have 1,800 mental health worker vacancies just in L.A. County — there is real commonality there.

I talked with a young farmer in the Central Valley in California named Nevin, who started his own dairy farm, getting out of the commodities farming that his family came from. And I was in a conversation with Senator [Charles E.] Grassley [a Republican] from Iowa talking about the state of climate change and how water and the lack of water and sometimes the abundance of unplanned water is having an impact on farmers in Iowa. The same dairy cows that Nevin is farming in the Central Valley in California are impacted by those things.

And so seeking to find common solutions in which every American can see themselves is, I think, the greatest opportunity that we have. But it is grounded in the articulation of those frustrations and listening to them, listening to those frustrations and intentionally seeking those places of common ground.