

Senator Rand Paul (R-Ky.) shakes hands with a guest as he signs copies of his book "Government Bullies" at the Conservative Political Action Conference (CPAC) in Oxon Hill, Md., in March. (Mike Theiler/Reuters)

Sen. Rand Paul (R-Ky.) in recent days said he doesn't blame President Obama for the situation in Iraq and suggested that U.S. foreign policy is fomenting extremism in the Middle East.

Needless to say, this isn't your average Bush-Cheney era Republican.

Now that the stage has been set for a foreign policy clash between Paul and the likes of Cheney, and as Paul approaches a 2016 presidential bid, it's worth asking: How much of today's Republican Party is truly open to Paul's brand of foreign policy?

The answer: It could be plenty. Or it could be very few. And it depends a lot on what's happening in the world.

Let's take this step by step:

1) The GOP has definitely taken a turn for non-interventionism

Paul's father, former congressman Ron Paul (R-Tex.), ran for president twice on a "non-interventionist" platform that tended more toward isolationism than his son's. And it cost him any real chance at victory, effectively relegating him to a small but vocal minority of the GOP.

Perhaps the biggest question for the younger Paul heading into a likely 2016 campaign is whether he can avoid a similar fate with his own brand of non-interventionism.

The good news for him: Non-interventionism is catching on.

While there was near-universal support inside the Republican Party for both the wars in Iraq and Afghanistan, that faded over time in both cases. As of 2013, about four in 10 Republicans said that both the wars in Iraq and Afghanistan weren't worth fighting, according to Washington Post-ABC News polling.

And it's not just those specific wars — it's also military intervention in general.

A December study from Pew showed the percentage of Americans saying that the United States should "mind its own business" in foreign affairs reaching a half-century high. About half — 52 percent — agreed with this statement, while 38 percent disagreed.

Support for what was essentially a non-interventionist foreign policy was actually higher than it was during Vietnam or any other recent conflict.

A big reason for the uptick? Republicans.

While after 9/11, 22 percent of Republicans said their country should generally "mind its own business" internationally, today that number has risen to 53 percent — more than Democrats, in fact.

So Republicans are more non-interventionist than Democrats, right?

Well, not necessarily.

Part of the shift is undoubtedly tied to the fact that a Democrat is steering the country's foreign policy. That's just how things generally work — just like how Democrats were more non-interventionist when George W. Bush was in the White House.

But it's also clear that a majority of Republicans today at least profess to agreeing with some form of a "non-interventionist" foreign policy — something Paul-world is undoubtedly banking on.

But it's not quite so simple, because ...

2) This newfound GOP non-interventionism hasn't really been tested

The rise of non-interventionism in the GOP coincides with a whole lot of unpopular foreign policy pursuits. Of course there were the lingering wars in Iraq and Afghanistan, but there were also some unhappy choices to be made in Syria and Ukraine.

Given all of this, it's not surprising that Americans — and Republicans — would tend toward just staying home.

But the current situation in Iraq is testing this.

As I wrote this morning, Republicans are significantly more apt to say the United States should be getting more involved in that country, with a new CBS News/New York Times poll showing 53 percent calling for Obama to do more than he has done so far. Just 13 percent of Democrats and and 29 percent of independents agree.

On the other side of the coin, just 21 percent of Republicans want a less-involved — i.e. non-interventionist/mind-your-own-business — approach to the conflict. This seems to be pretty close to what Paul is espousing, though Paul did suggest that Obama's decision to send 300 soldiers as advisers might be okay.

So basically, when the rubber meets the road, it's pretty clear which party is more hawkish on foreign policy. And it's still the GOP.

It's easy to say the United States should mind its own business when wars are unpopular and people no longer seen the immediate urgency of overseas missions. The question for Paul is what happens when Republicans actually see a reason for foreign involvement that he doesn't necessarily agree with. As the CBS/NYT poll shows, the numbers can shift pretty quickly away from non-interventionism under the right circumstances.

3) The issue matrix matters ... a lot

So basically, whether Paul's foreign policy is palatable to most Republican primary voters depends a lot on which issues are on the table. As mentioned above, Iraq threatens to turn the tide away from GOP non-interventionism. But it's not the only issue.

Republicans are also more concerned than Democrats when it comes to China, Iran, North Korea and pretty much any perceived foreign policy threat.

A lot of the gaps above aren't that big, but you'll notice the biggest one is "Islamic fundamentalism" -- the very thing that a majority of Republicans see as growing as a threat in Iraq. According to CBS/NYT, 60 percent of Republicans see the situation in Iraq leading to a greater threat of terrorism against the United States, as compared to 36 percent of Democrats.

So if the question is: How big is the Rand Paul foreign policy wing of the Republicans Party? The answer is: It depends.

Right now, it's as big as it has been in a long time -- with upwards of half of Republicans sympathizing with his general philosophy. But whether that persists over the next two years depends a lot on what kinds of foreign policy issues are relevant.

And if the wrong issues are at the forefront and Paul errs too much on the side of non-interventionism, he could find himself marginalized.

Scott Clement contributed to this post.