When it comes to foreign policy, the 2016 Republican presidential race is often presented as a contrast between Sen. Rand Paul, R-Ky., and everybody else.

As the narrative goes, Paul has a record of advocating for less intervention in foreign affairs, while the rest of the field has endorsed a more muscular posture. But this is an oversimplification.

Though the differences Paul has with the rest of the party deserve attention, a far more interesting — and important — debate is the one likely to emerge between Sens. Marco Rubio of Florida and Ted Cruz of Texas.

On the surface, Rubio and Cruz are hard to tell apart on foreign policy. Both have harshly criticized President Obama for showing weakness to the nation's enemies and hostility toward allies. Both have argued for the importance of projecting strength abroad. Both have warned of the dangers when the U.S. cowers from promoting American values on the world stage. There won't be much daylight between the candidates when it comes to issues such as preventing a nuclear Iran and supporting Israel.

But scratch beneath the surface, and there are subtle but important distinctions that reveal a deeper debate on the right over the proper role for the United States overseas.

In a little-remembered speech he made back in March 2014, Cruz described how there weren't just two, but three sides in the foreign policy debate among Republicans.

"There is a lot of discussion about the differing views in the Republican Party and are Americans war weary?" Cruz observed at an off-site event during CPAC sponsored by Breitbart News Network and Frank Gaffney's Center for Security Policy. "Are we war weary and as the consequence to that, does that mean we are no longer willing to defend ourselves? I think that is a profound misreading of the American people."

He continued, "Now listen, I agree with many of the libertarian critics that the job of our military is not to intervene all around the world and to be the policeman for the world. And I'll give an example. The Republican Party — you can point to two points on two ends of the spectrum, where foreign policy views lie. On one side you have the views of John McCain. The other end of the spectrum, you have the views of Rand Paul. And I would note with respect, my views are very much the views of Ronald Reagan, which I would suggest is a third point on the triangle."

As a concrete example, Cruz went on to describe his opposition to launching a military attack on Syria. Though he described Bashar Assad as a "brutal tyrant," he said "the enemy of your enemy is not necessarily your friend. And just because he is a brutal tyrant doesn't mean the rebels are any better." He said radical Islamic terrorists infiltrated the rebel groups, and if Assad's regime fell, those terrorists could get their hands on chemical weapons, "an even worse outcome for U.S. national security interests."

He summarized, "My view, just like President Reagan on foreign policy, is if and when we are called to use military force, we should do so with a clear defined objective that is directly keyed off of U.S. national security. We should go in with overwhelming force. And then we should get the heck out. I don't think, and I think most Americans don't think, we should be engaged in nation building, building democratic utopias across the world."

In contrast to Cruz's views, Rubio has spent his Senate career largely allied with McCain. He's expressed optimism about the potential for the U.S. to help spread secular democracy in the Middle East and protect human rights. He backed U.S. intervention in Libya and argued for the goal of removing Libyan leader Muammar Qaddafi.

In an Oct. 2011 Wall Street Journal op-ed he co-authored with McCain (along with Sens. Mark Kirk, R-Ill., and Lindsey Graham, R-S.C.,), Rubio recounted a trip the senators took. "Last Thursday we arrived in Tripoli to the promise of a free Libya," Rubio and the other senators wrote. They also reported, "the Libyans we met want to build a secure, prosperous and democratic nation that rejects violent extremism, allies itself with America and our allies, and promotes the peaceful ideals of the Arab Spring."

Throughout 2013, Rubio advocated arming the Syrian opposition. While Cruz argued this would be counterproductive, Rubio insisted that the democratically-minded rebels could be differentiated from the elements linked to terrorist groups. In contrast to Cruz, who warned of an even worse outcome if Assad fell, Rubio argued in March 2013 that, "it's in the national interest of the United States for Bashar al-Assad to leave. It's in our national interest for that government to fall." More broadly, he said, "I think the United States has always stood on the side of human rights, should always continue to stand on the side of democracy."

Though Rubio eventually opposed Obama's call for military action — saying he didn't think it would be effective as proposed — even in doing so, he argued that the U.S. should support efforts by the Syrian people to topple Assad "and replace him with a secular and moderate government they deserve."

Though the philosophical contrast between Rand Paul and the rest of the GOP field may be starker and thus easier to describe, at the end of the day, no Republican president is going to adopt a foreign policy akin to Paul's in the near future.

Right now, a broader cross-section of Republicans are torn between the failures of the Bush administration's efforts to promote democracy in the Middle East and the perils of Obama's reluctance to project American power. That's why, ultimately, the debate between Cruz and Rubio is more relevant.