During a speech at Jerusalem's Israel Museum, President Donald Trump vowed to stand up to Iran and prevent the country from obtaining a nuclear weapon.

“Iran’s leaders routinely call for Israel’s destruction. Not with Donald J.Trump,” he said to thunderous applause.

Standing beside Israeli Prime Minister Benjamin Netanyahu, Trump said the U.S. is firmly committed to opposing Iran's nuclear program and halting their support of terrorists and militias.

On "Fox & Friends," John Roberts reported that the audience clearly had a "tremendous amount of appreciation" for Trump's remarks.

He explained that this is a notable policy shift from former President Obama, who tried to negotiate with Iran.

Roberts added that Trump told dozens of Muslim leaders over the weekend that Iran represents an "existential threat," not only to Israel, but to the entire Arab world.

Watch Roberts' report above.

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