Julián Castro says visiting Florida detention center is not 'a stunt'

Just hours ahead of the first Democratic presidential debate, former Housing and Urban Development Secretary Julián Castro joined the "Powerhouse Politics" podcast and expressed that he plans to press his case for decriminalization of illegal border crossings when he takes the debate stage on Wednesday.

Castro admitted to ABC News Political Director Rick Klein and ABC News Chief Congressional Correspondent Mary Bruce that his name recognition is not currently as high as some other candidates, but said he hopes that by the end of the debate, people will better understand his experience and vision for the country.

"Right now, it's, 'articulate your vision for the future of the country and your answer on these important issues that you're facing in one minute,' and I'm going to try and do that tonight," Castro said.

In preparation for the debate, however, he was trying to relax.

"It's important to also not to over-prepare for something," he said Wednesday. "Tonight is also about being in the moment and being able to relate to people just on a human level and not be over-programmed, and so I'm going to mostly relax today."

Castro has tried to distinguish himself from among the other candidates on immigration and released an extensive immigration policy proposal in early April, in which he called for the decriminalization of illegal border crossings.

Such a move, Castro said, would make illegal border crossings a civil penalty instead of a criminal penalty. This is in contrast to President Donald Trump's zero-tolerance policy towards people who enter the U.S. illegally which demands every adult to be prosecuted, even if it requires separating families.

"The only way to make sure that we end family separation is to go from it being a criminal offense to it being a civil offense," he said.

On Tuesday, following reports of unsanitary and unsafe conditions at detention centers holding unaccompanied minors, Sen. Elizabeth Warren, D-Mass., came out in support of Castro's policy idea, though she has yet to release an immigration policy proposal of her own.

"I'm glad that Senator Warren supports the idea of making this a civil offense," Castro said. "It will mean, guaranteed, that we won't have these family separations again. It doesn't mean that there's not a court process that people are still involved in, they are. It's just a much more sensible way to do this."

Castro announced plans to visit the Homestead Child Detention Center outside of Miami on Friday. Homestead is a private facility where children have already passed the border protection process in comparison to the detention facilities discussed in the news such as those in Clint, Texas. Several candidates have visited and are also making plans to visit this week.

When asked whether visiting the Homstead facility is a stunt to highlight the issue, Castro replied that he doesn't think the visit comes off as a stunt and instead said they are calling attention to the issue behind private facilities housing undocumented minors.

"I wouldn't call it a stunt, I would say they were calling attention to the fact -- number one -- that we need to end this kind of detention and make sure that people can get to, either family members who live in the United States or caregivers who are willing to take care of them, as soon as possible," Castro told Klein.

Castro also spoke about the tensions in Iran and said it's the current administration that got the U.S. "into this mess."

"The problem is that this president has gotten us into this mess in the first place. The reason that everybody is talking about the big failure of this administration, when it comes to the Iran nuclear deal, is because two years ago we had a deal in place that everybody acknowledged was the strongest deal ever put together to make sure that a country did not develop a nuclear weapon," he said. "And then this president came along, and he radically haphazardly tore up that agreement. And now, because of that, we're in the mess that we're in. I believe that we should work with our allies to pressure Iran to do what we want them to do."

With regard to former special counsel Robert Mueller's decision to testify before two House committees next month, Castro said that he is glad people will hear Mueller testify. He added that he doesn't believe impeachment should be viewed as a political move.

"I'm glad that the American people are going to be able to actually hear his testimony. And when they hear his testimony, I think it's compelling that this president should be impeached," Castro said. "I don't think we should see this as something political because we need to say that nobody is above the law, especially the president of the United States."

ABC News' Armando Garcia and Lissette Rodriguez contributed to this report.

Powerhouse Politics podcast is a weekly program that posts every Wednesday, and includes headliner interviews and in-depth looks at the people and events shaping U.S. politics. Powerhouse Politics podcast is hosted by ABC News Chief White House Correspondent Jonathan Karl and ABC News Political Director Rick Klein.