National security expert sounds alarm over Biden’s health: 'Can't have a part-time commander-in-chief'

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Former Trump national security official Gen. Keith Kellogg (Ret.) sounded the alarm about President Biden's fitness for a second term, warning that the U.S. cannot have a "part-time commander-in-chief" as Biden prepares to address NATO leaders.

"Let's go back to the Federalist Papers, back when we were forming the Constitution, and Alexander Hamilton was asked a question, and he wrote in the Federalist Papers, ‘What is one of the key attributes of a... national leader?’ And he said, energy, and he was talking both intellectual energy and physical energy," the former Army lieutenant general told Steve Doocy during "Fox & Friends" on Tuesday.

"So you even go back to the start of our republic and what was essential for a commander-in-chief. You can't have a part-time commander-in-chief."

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The former national security adviser to VP Mike Pence noted the importance of making split-second decisions at any hour, a capability called into question by both Democrats and Republicans alike after the president's debate performance.

"I cannot tell you how many times we had to wake… President Trump up, in the middle of the night, to have a decision, and he was right on it right away," he said. "Look, that time when we killed Soleimani, we woke him up in the middle of the night.