Retired four-star General Frank McKenzie, the former commander of U.S. forces in the Middle East, said on Sunday that Iran was seriously trying to assassinate former President Donald Trump out of a place of “desperation” because they view him as a threat to their regime.

McKenzie made the remarks during a CBS News interview with Margaret Brennan on “Face The Nation” while discussing what Israel’s response should be to Iran’s ballistic missile attack last week.

“The principle goal of Iranian statecraft is regime preservation,” he said. “They view the election of President Trump as a direct threat to that regime preservation. So, I have no doubt believing that Iran is very active in its attempts to go after the former president, as well as other officials, of which I am keenly personally interested as well.”

“What’s driving their behavior is desperation,” he continued. “It’s actually the same sort of desperation that drove the massive attack on Israel of three or four nights ago. They’re in a corner, and they really don’t have any good options. But they don’t want to sit still and do nothing. They do view President Trump as worse than the alternatives that could be elected.”

On the matter of how Israel should respond to the attacks, he said that they had a wide range of options.

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“They can choose for something that would be very escalatory in terms of a strike against the supreme leader himself perhaps or against the nuclear program or against the oil infrastructure, or they could look at military intelligence targets,” he said.

He said that it will be difficult for Israel to take out Iran’s underground nuclear facility, which is buried nearly 250 feet under a mountain, because the U.S. is the only country that has large enough bunker-buster bombs to reach the target.

He also slammed the Biden-Harris administration for saying that Israel should not hit Iran’s nuclear facilities.

“You should never take a potential target off the menu,” he said. “You want your adversary to have to plan to defend everything. Giving him assistance and not having to defend against a particular target is probably not the best way to establish this kind of deterrence.”

He said Israel should definitely consider going after Iranian oil infrastructure and going after the “Islamic Republican Guard Corps headquarters and intelligence buildings all around Tehran or anywhere else.”

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