Rand Paul is on a tear.

The junior senator from Kentucky did not mince words when a fellow Republican freshman, Florida Sen. Marco Rubio, waved the bloody shirt against the Obama administration on Cuba.

On social media and in the pages of Time, Paul dusted off an epithet frequently employed against him and instead used it against his enemies within the party. He called Rubio and others committed to maintaining unilateral trade and travel restrictions against Cuba long abandoned by most of the rest of the world “isolationists.”

After all, Paul reasoned, who else is really committed to isolating the United States?

Paul wasn’t done yet. He taunted Rubio for wanting to “retreat to our borders and perhaps build a moat.” He asked why the United States could trade with China and Vietnam but not Cuba. He cited polling that suggests Cuban-American opinion on normalizing relations with Havana is at the very least not so monolithic.

In so doing, Paul has excited his libertarian base. He has also differentiated himself from a 2016 Republican presidential field mostly committed to the status quo when it comes to dealing with the Castros’ island gulag, a communist dictatorship that has outlived the Soviet Union by nearly a quarter century despite the United States’ best efforts.

If our Kennedy-era Cuba policies are a success, then it is hard to pronounce many liberal relics of the Great Society a failure. And even to the extent that there was some national-security justification for this approach at the height of the Cold War, we are living in a very different world as 2014 comes to a close.

One need not think trade and travel are a panacea–China perfectly illustrates their limits–to suspect that Paul is right to look beyond the rhetoric that will help him win the Florida primary.

But Rand Paul is undeniably taking a risk. Paul has had his greatest successes at moving the Republican foreign-policy debate when instead of challenging his party’s premises and prejudices, he has tried to demonstrate how conservative ends could be better served by less interventionist means.

There’s a reason rank-and-file Republicans have been more willing to give Rand a hearing than his father.

Paul has also been most successful at persuading Republicans to entertain his realist prescriptions when his policies were clearly not Barack Obama’s: drones, presidential kill lists, Syria, Libya.

It’s easy to make the case that all these things constitute a form of government overreach. It’s even easier when they have the fingerprints of the president behind Obamacare all over them.

But on Cuba and Iran, it is now equally easy–and in Republican primaries, politically perilous–to link Obama and Paul.

Conservative antipathy toward these governments deservedly runs deep, even if the policies pushed by hawks to satisfy this sentiment remains deeply flawed.

As the primaries approach, Paul is increasingly positioning himself as someone willing to tell his fellow Republicans things they don’t want to hear. That extends to
Ferguson and voter ID as much as Russia and Cuba.

In 2012, the candidate most likely to tell Republican primary voters what he thought they wanted to hear was Mitt Romney. The Republican after Ron Paul who was least likely was probably Jon Huntsman. It goes without saying who became the nominee.

Paul is also in direct competition with Republicans like Ted Cruz for the Tea Party vote. As such, he is more dependent on favorable coverage from the conservative media and the perception that he is more simpatico with the base.

None of this is to suggest that Paul should run a Romney-like campaign. The point is merely to note that some degree of common ground is important for political persuasion.

Many of Paul’s conservative and libertarian supporters have long wanted him to wage a full frontal assault on the Republican Party’s reigning foreign policy. They felt that if anything, Paul was too quick to accede to the hawkish conventional wisdom on issues like Iran sanctions and confronting the Islamic State in Iraq.

These Paul sympathizers make the entirely reasonable point that for Republicans to start listening to a different set of foreign-policy arguments, they first have to hear them.

If Rand Paul’s gloves-off Cuba fight is any indication of things to come, we’ll soon find out which strategy works best.

W. James Antle III is editor of the Daily Caller News Foundation and author of Devouring Freedom: Can Big Government Ever Be Stopped?