'Biden is right': Trump's former defense secretary warns CNN about ex-boss's second term

Mark Esper, the former secretary of defense under Donald Trump, warned that foreign leaders are "concerned" and "bracing" for his one-time boss's return to office.

During a Wednesday interview on CNN, Esper explained why President Joe Biden was "right" about foreign policy and national security.

"If Trump is re-elected, will he reduce the U.S. role in NATO?" CNN's Jessica Dean asked Esper. "He has said, he's made a lot of passing comments about it, said that if countries in Europe aren't paying their fair share, that Russia and Putin can do whatever they want to them, things like that. How do you think that these domestic politics could potentially affect the global stage?"

Esper said foreign leaders often asked him about the status of the U.S. presidential race.

"What will Trump do?" Esper recalled being asked. "How does he look upon our country, this alliance, whatever the case may be?

"And those fears have only grown exponentially here in the last few weeks," the former defense secretary continued. "And, you know, we wake up this morning, we see new polls saying that states that were in a lean Democratic bucket are now toss-ups and ones that were likely Democratic are now leans [Republican]."

"They see Joe Biden's disastrous debate, and they're bracing, bracing for what may come."

Esper reminded Dean that Trump "will not support Ukraine."

"He has threatened in the past to withdraw from NATO and he can do any number of other things," he explained.

"Does that concern you?" Dean wondered.

"Well, yeah, it deeply concerns me because, look, the world is under a lot of stress these days," Esper replied. "There's conflict breaking out everywhere."

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"President Biden is right," he added. "This is an era where the democracies are facing against, facing off against the autocracies of the world."

Esper argued that America needed to "lead on the world stage."

"Bearing that leadership is a heavy burden, I know, but it's very important if we want to maintain a stable, prosperous, global order, one that is based on our values and interests, much like we have the last 75 years for the next 75 years going forward," he insisted. "There's a lot at stake."

Watch the video below from CNN.