East Palestine, Ohio, Mayor Trent Conaway took the stage, praising the first responders who rushed to help after a freight train carrying hazardous materials derailed last year.

He criticized the federal response, claiming the Biden administration "talked and talked, but they delivered little help."

Conaway went after Biden for not visiting the town in the immediate aftermath and praised Trump for coming to the town less than three weeks after the incident.

"I know a thing or two about train wrecks now and let me tell you, that is what the Biden administration has been," he said.

In an exclusive interview with ABC News anchor David Muir in February 2023, Biden said he "made it clear" to officials on the ground that "anything they need, we'll make it available to them."

The comments came after East Palestine's mayor called it a "slap in the face" that Biden traveled to Ukraine while his town felt forgotten in the weeks after the crisis. Biden went to East Palestine a year later.

The title for this session is "Make America Strong Again," with speeches centered on foreign policy and national security.

Speakers have discussed China, Russia and energy policy.

But immigration, specifically border security, has stoked the most audience reaction -- with attendees often waving "Mass Deportation Now!" signs.

"Send them back!" chants started as Texas Gov. Greg Abbott spoke about bussing migrants to Democratic cities.

Texas Gov. Greg Abbott touted President Trump's border policies and his own as the largest border state governor in the country. The governor received a raucous reception at the RNC.

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Abbott says Trump will secure border

Texas Governor Greg Abbott touted former President Trump’s border policies and his own as the largest border state governor in the country. The governor received a raucous reception at the RNC.

He defended his orders that the Texas National Guard install razor wire across parts of the Texas border and his policy of bussing migrants out of Texas and north. (A narrowly divided Supreme Court in January sided with the Biden administration in a tense, ongoing dispute over the Texas-Mexico border and razor wire fencing installed by the state that had prohibited federal border agents from performing their duties.)

"The president's most sacred duty is to secure our country," Abbott said. "Joe Biden deserted his duty," the governor argued.

"It is time to restore order at the border, to rid our streets of crime and chaos; it is time to secure our nation by returning Donald Trump as president of the United States of America," he said.

As Jim and Sue Chilton took to the stage to talk about their experience as Arizona ranchers operating near the border, chants of "build that wall" erupted in the arena.

Building a border wall from coast to coast was a key priority for Trump in his first term, though he implemented just roughly 450 miles of barriers -- much of which was upgrading existing barriers that already existed.