It’s a term Rand Paul has rejected when applied to his own foreign policy.

But on Friday, the libertarian-leaning Republican senator referred to Florida Sen. Marco Rubio, a potential opponent in the 2016 GOP presidential primary, as an “isolationist.”

Discussing their differing opinions on Cuba, Paul wrote on Facebook: “Seems to me, Senator Rubio is acting like an isolationist who wants to retreat to our borders and perhaps build a moat. I reject this isolationism.”

“Senator Marco Rubio believes the embargo against Cuba has been ineffective, yet he wants to continue perpetuating failed policies,” Paul said. “After 50 years of conflict, why not try a new approach? The United States trades and engages with other communist nations, such as China and Vietnam. Why not Cuba? I am a proponent of peace through commerce, and I believe engaging Cuba can lead to positive change.”

Added Paul: “Finally, let’s be clear that Senator Rubio does not speak for the majority of Cuban-Americans. A recent poll demonstrates that a large majority of Cuban-Americans actually support normalizing relations between our countries.”

Appearing on Fox News on Thursday night, Rubio said of Paul’s view that President Obama did the right thing to open relations with Cuba: “Well, like many people that have hit on it, he has no idea what he’s talking about.”

“And I’ll tell you why; number one, the embargo on Cuba is an embargo that frankly has a bunch of holes in it,” Rubio said. “To give you an example, the United States is still one of Cuba’s largest trading partners, even now with the embargo.”

“What’s hurting the Cuban people is not the embargo,” Rubio added, appearing on Megyn Kelly’s show. “What’s hurting the Cuban people is the Cuban government.”

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