A dispute between Sen. Rand Paul and Sen. Marco Rubio over U.S.-Cuba policy is escalating. The dispute began late last week after Rubio criticized what he described as capitulation by Obama. Paul responded in a radio interview, an op-ed, and via Twitter:

Hey @marcorubio if the embargo doesn't hurt Cuba, why do you want to keep it? — Senator Rand Paul (@SenRandPaul) December 19, 2014

Senator @marcorubio is acting like an isolationist who wants to retreat to our borders and perhaps build a moat. I reject this isolationism. — Senator Rand Paul (@SenRandPaul) December 19, 2014

The United States trades and engages with other communist nations, such as China and Vietnam. So @marcorubio why not Cuba? — Senator Rand Paul (@SenRandPaul) December 19, 2014

.@marcorubio what about the majority of Cuban-Americans who now support normalizing relations between our countries? http://t.co/0qhSOeD9Va — Senator Rand Paul (@SenRandPaul) December 19, 2014

Rubio responded earlier today by saying that Paul is Obama’s chief cheerleader on foreign policy:

Sen. Marco Rubio responded to criticism from fellow Republican and potential 2016 presidential rival Sen. Rand Paul over his position on Cuba, insisting today that he would oppose the “Obama-Paul foreign policy,” and referring to the Kentucky senator as “chief cheerleader” of the president’s overseas agenda. “Rand, if he wants to become the chief cheerleader of Obama’s foreign policy, he certainly has a right to do that,” Rubio, R-Fla., told ABC’s George Stephanopoulos on “This Week.” “I’m going to continue to oppose the Obama-Paul foreign policy on Cuba because I know it won’t lead to freedom and liberty for the Cuban people, which is my sole interest here.”

Minutes ago, Sen. Paul posted the following tweet, which seems to take the dispute to a new level:

.@marcorubio forgot to mention his support for Obama's funding of Musl. Brotherhood, arming Islamic rebels, and Hillary's war in Libya. — Senator Rand Paul (@SenRandPaul) December 21, 2014

Whoa. Twitchy cannot recall such a fierce attack tweeted by one sitting U.S. Senator to another.

Clearly there is no love lost between these two Senators. Nevertheless, some readers are urging the two to put their differences aside and focus their fire on Democrats:

@SenRandPaul @marcorubio Let's turn our attention to the OTHER side, the Democrats, remember?? Friendly fire is not a good thing. — John Fleming (@jcfdal) December 21, 2014

@SenRandPaul @marcorubio Oh FFS. Shut up Rand. Hiding behind Twitter to bash another Senator. Pretty weak and cowardly IMO. — Addie (@JrsyGirl87) December 21, 2014

Related:

Rand Paul slams ‘isolationist’ Marco Rubio for wanting to ‘perhaps build a moat’