During the segment, host Jen Psaki brought up Trump’s recent attacks and asked Booker what message he had for whistleblowers and others speaking out in a tense political environment.

“Trump attacked you today,” Psaki said. “You’re in elected office. You accept that, I know. But what do you say to people? What is your message to whistleblowers or people whose stories are so important to tell about why they should do it now, and what impact it could have?”

Booker didn’t hesitate. “Stand up and fight,” he said.

“I’m going to continue to fight,” he added. “I don’t care if this president calls me out every day, mean tweets me, threatens me.”

Booker pointed to arrests of officials in Newark as part of what he described as a broader effort to intimidate.

“We know I’ve had open conversations with senators I never thought I would have because we saw what they’ve done with a congressperson,” he said. “My Congresswoman LaMonica McIver — arresting her. My mayor — they’ve arrested. They’re picking off, it seems, people that live in Newark that are in elected positions. But I don’t care. Throw me in jail. Do what you have to do. I’m going to continue to stand up for what’s right.”

He ended with a call for others to join him.

“I’m hoping that when one person stands up and calls this out, it ignites the courage of another person and another person and another person,” Booker continued. “We have to, at a time that our fundamental rights and freedoms — that the very democracy we know is precious — is under attack by this president. We’ve got to have more people willing to stand up and fight and take him on.”