Oakland Mayor Libby Schaaf used her office to alert the public to a federal immigration sweep.

That’s what she did, make no mistake about it. And it was brilliant. Politically risky, yes. But Schaaf stood up to hate.

It’s caused a stir — U.S. Immigration and Customs Enforcement officials suggested Schaaf’s warning helped many undocumented immigrants avoid a sweep that resulted in 150 arrests. But Schaaf’s not backing down. And she shouldn’t.

We are taught as Americans to speak up and not stay silent in the face of hate and unfairness.

“Trump’s fearmongering, his attempt to paint all immigrants as dangerous criminals, is racist,” Schaaf told KQED’s “Forum” on Wednesday.

The president, who gorges on rage politics, helms an administration that is as spiteful as it is dysfunctional. When he announced his candidacy by declaring that Mexican immigrants were rapists, he telegraphed his political stance on communities of color. His unapologetic and uninformed verbal assaults on Muslims and blacks have energized white supremacists.

Schaaf’s the mayor of a diverse sanctuary city with a large immigrant population, and since the presidential election it’s become a city where some residents are besieged by fear and intimidation as families are ripped apart.

“When an official has information that could help people, it’s their duty to share it,” Schaaf told me. “Having information before an ICE action can make a tremendous difference.”

In a statement, Thomas Homan, the acting director of ICE, said Schaaf had endangered ICE officers, an announcement that once again advances the government’s narrative that all undocumented immigrants are criminals to be considered dangerous.

How does working to feed your family pose a threat to public safety and national security? Most people come here for an opportunity at a better life, much like the European settlers who first came to America, a land already inhabited by indigenous people.

But aren’t undocumented people breaking the law of the land? Yes, but in this country laws have been enacted — or ignored — to disenfranchise and oppress people of color since it was founded. The Declaration of Independence, written by white slave owners and white men who profited from slavery, says that all men are created equal.

Equality can only be imagined in this country. But the fight for it, and for what’s right, must continue.

We must stay vigilant, like Schaaf.

Eleni Wolfe-Roubatis, immigration program director of Centro Legal de la Raza, an Oakland nonprofit that provides legal support for immigrants and others, said that since Schaaf’s warning, her office has been buzzing.

And this breaks my heart: Children have called, wondering whether it was OK for them to go to school because they were worried their parents would be taken while they were in class.

“There is a constant fear in the community that ICE actions are going to be happening, so I think that’s very present in people’s minds,” Wolfe-Roubatis said. “I know we’re paying more attention to them now in terms of the media and politicians and others, but this unfortunately is every day for ICE.”

Every day ICE is knocking on doors and detaining people. Every day.

Think about what happens in detention, the inhumane treatment some detainees have endured before being deported. I’ve reported on what some women have encountered at the West County Detention Facility in Richmond, and I’m in the midst of reporting for an upcoming column about the physical torment one man suffered at the facility.

We’re at an immigration code red, and Schaaf was right to sound the alarm.

Now let’s make sure we have her back.