Athens, Georgia - Vice President JD Vance was heckled repeatedly at a half-empty Turning Point USA event while he attempted to lecture Pope Leo XIV on Catholicism and war.

Amid an unprecedented clash between the pontiff and President Donald Trump, Vance – a self-described devout Catholic – took it upon himself to explain why Leo's condemnations of US and Israeli warmongering in the Middle East was wrong.

"How can you say that God is never on the side of those who wield the sword?" Vance said in respond to the pope's decision to advocate for peace. "Was God on the side of the Americans who liberated France from the Nazis?"

It was at this point that the heckling started, coming from an audience member in the middle of the auditorium, which videos of the event showed was half-empty.

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"Jesus Christ does not support genocide," a person called out from the crowd as Vance was speaking. "Why are you committing genocide in Gaza?"

Vance first brushed off the accusations and then lost his cool.

"First of all, random dude who's shouting, can I finish my point and then I'll respond to what you just shouted," Vance insisted, before saying that the pope should be "careful when he talks about matters of theology."

"When we came in, the humanitarian situation in Gaza was an absolute catastrophe," he said, before pointing blame at the Biden administration for Israel's destruction of Gaza, which constitutes a genocide according to a consensus of experts.

"You know who's the person who got a peace agreement in Gaza? Donald J. Trump," Vance claimed.

Despite a nominal "ceasefire" agreed in October last year, Israel has continued kill Palestinians in the enclave on a near-daily basis, while forcing the population into ever-smaller areas and denying the entry of aid.

Vance's appearance at a TPUSA comes the same week that Trump and Pope Leo XIV have engaged in a public spat over the US and Israel's violent attacks on Iran.