DeSantis expressed support for using the U.S. military to combat drug cartels across the border.

"The president of the United States has to use all available powers as commander in chief to protect our country and the people," DeSantis said.

"When they are coming across, yes we are going to use lethal force," he continued -- a line he's used repeatedly throughout the campaign.

Activists have pushed back that his plan is inhumane and illegal.

-ABC News' Alexandra Hutzler

Martha MacCallum just asked about what to do about migrants already in the United States. In a July poll by The New York Times/Siena College, 39 percent of likely Republican voters say that they supported a “comprehensive immigration reform bill that provides a pathway to citizenship for all undocumented immigrants” in the United States, while 57 percent opposed such a bill. Support was weakest among Trump supporters (29 percent) compared with DeSantis supporters (48 percent) and voters who say they will vote for another candidate (50 percent).
-Analysis by FiveThirtyEight

While many candidates onstage have sparred with each other -- including Haley and Ramaswamy swapping sharp words on foreign policy -- Scott has yet to engage with any of the other candidates.

Much of his remarks have almost word for word repeated elements from his campaign stump speech. When asked about China, which he has addressed in other appearances, he pivoted to speaking about the U.S. border.

-ABC News’ Gabriella Abdul-Hakim and Oren Oppenheim

Asked to raise their hand if they would not increase aid to Ukraine, DeSantis did so, saying that "Europe needs to step up. They need to step up and do their job."

He argued: "I would have Europe pull their weight. ... Our support should be contingent on them doing it.

DeSantis -- who had received backlash from some other politicians for seemingly backtracking on support for Ukraine -- pivoted to say that he wasn’t going to send troops overseas but rather down to the Southern border.

-ABC News' Hannah Demissie and Will McDuffie

Members of DeSantis’s campaign are still upset about a debate memo that was prepared and published last week by a super PAC supporting the governor, a source close to the campaign told ABC News on Wednesday, describing those members of his team as “wildly irritated.”

Chief among the complaints is that the memo, which detailed suggested approaches and lines of attack, effectively handcuffs DeSantis by preventing the governor from using any of the advice on stage lest he invite attacks from opponents for using lines manufactured for him by other people.

The memo included research documents that show that Axiom Strategies, a consulting firm tied to the super political action committee, anticipated that the biggest hits to DeSantis would include his battle with Disney -- ABC News' parent company -- past comments on Ukraine, Florida's Black history standard, the culture wars and abortion.

The packet also included past comments made by presidential hopefuls attacking DeSantis on those specific subjects.

DeSantis himself has downplayed the memo, telling Fox News recently, “It’s not mine. I haven’t read it. It’s just -- I think it’s something that we have put off to the side.”

-ABC News’ Hannah Demissie, Will McDuffie and Olivia Osteen