During CNN's Wednesday night town hall with Florida lawmakers, survivors of last week's high school shooting and members of the NRA, Sen. Marco Rubio attempted to explain why a ban on assault rifles wouldn't have prevented the tragedy, and the audience's reaction was not quite what he was hoping for.

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While explaining what a ban on assault rifles would do, the Republican senator from Florida said to ensure no one would “get around it.”

“You would literally have to ban every semi-automatic rifle that’s sold in America.” A surprised Rubio, who appeared to have been hoping to convince the audience against such an idea, was met with a solid 10 seconds of applause that overwhelmed the room.

“Fair enough, fair enough,” the senator said as the cheers died down.

The moment came just after a grieving father called Rubio's reaction to the mass shooting "pathetically weak" and asked whether the senator would support banning assault rifles like Nikolas Cruz's AR-15 in order to save the lives of children.

“It’s too easy to get. It is a weapon of war,” the father emotionally said. “The fact that you can’t stand with everybody else in this building and say that, I’m sorry.”

A flustered Rubio assured him, “I do believe what you’re saying is true,” before launching into his argument against an assault rifles ban.

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CNN's town hall follows last week's shooting at Marjory Stonemason Douglas High School where gunman Nikolas Cruz fatally shot 17 people and injured over a dozen more. In the time since, many of the school's surviving students have been commanding public attention and demanding a conversation about gun reform in the United States.

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