Massachusetts Sen. Elizabeth Warren has been at the forefront of progressive politics over the last year.

She has sparred with President Trump on Twitter, and she was reprimanded by Republicans on the Senate floor earlier this year. Now she has written a new book, This Fight Is Our Fight: The Battle To Save America's Middle Class.

Warren tells All Things Considered that she sees Trump's rise as part of a larger narrative of economic inequality in this country. She argues that the government's lack of investment in the middle class created the conditions "where Donald Trump could deliver the knockout blow."

"Are we just going to let Donald Trump and these Republicans in Washington just totally turn our government over to those with money and power?" Warren asks. "The rich and the powerful have been running our government for about 35 years now, and they have really made it work great for those at the top — for everyone else, not so much so. What I argue in this book is it is time for the rest of us to fight back, all of us, and that we can do it, and we can make our voices heard."

As for criticism that the Democratic Party has not always held up its end of the deal for American workers, Warren says "there's truth in that."

"Look, let's be blunt. Democrats have not always been on the right side of these arguments," she says, "and frankly Democrats have not indicated always a willingness to wade in and actually to fight for the people who need it."

Interview Highlights

On the decline of the middle class

I see this as a problem that is framed in a much longer arc, and it's the story I try to tell in my book, This Fight Is Our Fight. It's about how [gross domestic product] has gone up in this country from 1935 to the present day. But there was a time in America when we were investing, using that money to invest in America's middle class. And from 1935 to about 1980, that's what it was. We built a solid middle class.

And then starting in 1980 forward, what happened was that we started taking the legs out from underneath it. Ronald Reagan comes in, it's trickle-down economics, it's tax cuts for those at the top, it's less money to invest in education and infrastructure and basic research, it's turn the banks loose to do whatever they want, it's deregulate the giant corporations in this country. And what happened was that America's middle class began to shake, began to crumble, and now we're in a place where Donald Trump could deliver the knockout blow.

On the Women's March and ongoing activism

Everybody's got to get out there and find the piece that they can do. To me, that's ... what the Women's March signaled. You know, watching all these folks who said, "Wait a minute. Democracy is not something I can hand over to someone else. Democracy is something I've got to do." ...

I tell the story in the book about — I did the Women's March in Massachusetts in Boston, and as we're turning the corner to go to the Common, you see all these people who are walking. You know, women in their pink pussyhats and men pushing strollers, kids running and people on bicycles. And I saw this little girl, and she was riding on her daddy's shoulders, and she's holding up this sign, and the sign said, "I fight like a girl." And I thought, "Me too, sweetie!" You know, she's in the fight. And this is where our army's gonna come from. Some people will run for office, some people will help those who are running for office, some people will be the one who makes the phone call, show up at the rallies. But it's gonna take all of us in this fight.

On whether she will run for president in 2020

I don't have any plan to do that. I'm running for the Senate in 2018 for Massachusetts. But I gotta say this one more time: This is not about what happens every four years, or what happens four years from now. We have to be in this fight right this minute. This is what has changed in democracy in America. It's not the case that we can simply put this off, you know, and every four years we'll all kind of get interested in one big race and pay attention to it — or maybe every two years for congressional races or Senate race. No. No longer can we do this. We have to be engaged, and we have to be engaged right now. I mean, between now and the end of the day. It's what Donald Trump is doing today and tomorrow and this week and next week. We gotta begin this fight now. That's why I wrote this book.

All Things Considered producer Becky Sullivan contributed to this report.

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