Rand Paul and Marco Rubio may be the two most prominent Tea Party freshmen in the Senate but their foreign policy views are an ocean apart—and things are starting to get testy.

Last week, Paul single-handedly blocked an amendment proposed by Senator Marco Rubio that sought to advance Georgia's application for NATO membership. It was a disagreement between two Republicans that would've gone largely unnoticed except for the fact that yesterday, Jack Hunter, the co-author of Paul's book The Tea Party Goes to Washington, ripped the lid off the dispute in a column for The Daily Caller.

Besides praising Paul for blocking the amendment, which Hunter says had bipartisan support, the article slams Rubio for failing to focus on the nation's pressing domestic issues. "Last week, while most senators were focused on the important national issues of war funding and Americans’ constitutional liberties, Senator Marco Rubio (R-FL) seemed more concerned with the fate of a foreign country."

The article also criticizes Rubio for dangerously entangling the U.S. in the affairs of other countries. "Make no mistake: Bringing Georgia into NATO could lead to a new military conflict for the United States," read the column. "Rubio’s attempt to push this through by unanimous consent — that is to say, without any formal debate or vote — is highly suspect and calls into question the senator’s better judgment."
 
Shortly after The Daily Caller story was published, Paul's Twitter account retweeted the link to it.  We asked Paul's office if the Kentucky senator and Hunter collaborated on the story, which chronicles an insider dispute*, but the office did not respond by press time. 
 
The details of Rubio's amendment called for President Obama to lead a diplomatic effort seeking approval of Georgia's Membership Action Plan at a NATO Summit in Chicago in May 2012, a precursor to NATO ascension that Russia has long-opposed.
 
Rubio's spokesman Alex Conant emphasized that the amendment did not go as far as some have alleged. "The Senator offered this  amendment in an effort to enhance Georgia’s ties with NATO," reads an e-mail to The Atlantic Wire. "It notably does not call for Georgia’s ascension to NATO."
 
As for the columns other allegations, Conant said "I don't have any response to the piece." 
 
The takeaway? Though both Paul and Rubio rolled into Congress under the Tea Party banner, the movement's non-interventionist and hawkish split personalities are finally beginning to show.
 
*An earlier version of this story neglected to mention that The American Spectator's W. James Antle reported on Rubio's disagreement with Paul on Monday.