Sitting in for Glenn on radio Tuesday, John Cardillo spent time discussing a threat he said isn't talked about nearly enough.

"If we sealed the borders tomorrow, if somehow we were able to wave a magic wand and we were able to build a 20-foot wall around the United States and we were able to mine every harbor and do these Draconian unconstitutional things, we still would only make a slight dent in a terror threat," Cardillo said.

Listen to the segment or read the transcript below.

JOHN: So we've been talking this hour about terror and some of the false narratives you've been sold by the progressive left, with regards to vetting of refugees, and regards to profiling of bad guys, no matter who those bad guys are, whether they be Islamic terrorists or La Cosa Nostra, the Italian mob. I don't discriminate. Bad guys who want to hurt people are bad guys. I want to deploy the best tactics to stop them.

But one of the things we don't speak about enough -- and I'm guilty of this as well on my show. I touch on it. But I don't touch on it anywhere near enough is a threat that's right here at home.

See, if we sealed the borders tomorrow, if somehow we were able to wave a magic wand and we were able to build a 20-foot wall around the United States and we were able to mine every harbor and do these Draconian unconstitutional things, we still would only make a slight dent in a terror threat.

And you're saying, Cardillo, you're out of your mind, what are you talking about? You sound like a crazy conspiracy theorist.

Well, no, I'm not. Because one of the things you don't hear enough about are the radical converts in prisons.

Remember, we have a very large prison population in the United States.

Now, about a year and a half ago, I had Pat Donely (phonetic) on my show, and he's a world expert with regards to prison conversion to Islam, the radicalization and weaponization of those converts. He spent about 30 years at New York City Department of Corrections. He's written several books on this and then worked with our intelligence community, training special operators on how to identify those who might be converts for America on the battlefield overseas.

And when we first spoke, I said, well, you know, I'm reading that there are about 30- to 40,000 people who convert to Islam yearly in US prisons and jails. Right? Prison is different from jail. Jail is that holding facility for misdemeanors. And before you face trial, prison is where you go after convicted.

So whether it be federal, state, local, about 30- to 40,000 people convert yearly. And I said to him, "Well, you know, how many though do you think would radicalize and weaponize?" And he said, "Oh, it's one percent or sub one percent." And I said, "Okay. Well, that's still a lot. That's still 3- to 400 people. The Orlando massacre at the gay club was carried out by one guy. San Bernardino by two terrorists. So 3- to 400 terrorists, half of which let's say might potentially be released from incarceration is pretty scary. Well, about eight, nine months later, had him on the show again, and that's his day-to-day job. He studies this. He trains our special operations community, our intelligence community.

I said, "So, Pat, is the number still hanging around 1 percent?" He said, "No, that number is creeping up to 10 percent," with the proliferation of ISIS's virtual caliphate and how well they're using social media and how they're spreading their message and going after a younger subset.

And so now let's think about how terrifying this is, right? If tomorrow, we were able to stop, 100 percent of the immigration -- from everybody. Forget even those from the 34 nations -- from everybody. Somebody that isn't in the US as of right now, never stepped foot in our nation and we were able to somehow wave a wand and get rid of everyone who would ever come here who happened to commit acts of terror, we would still be converting in our prisons and jails yearly about 3,000 people with the potential to radicalize and weaponize against us. And, again, I'm being conservative when I say half will be released shortly after that.

The number is a lot higher because our jails are overcrowded and we tend to release prisoners long before they should be. So while we're so focused on the refugee problem -- and we need to be. We need to be diligent. We need to be vigilant.

While we're focused on that, we also need to keep our eye on the ball here at home. Because if we don't do that, if we put ourselves in a position where we ignore the threat that's already here, where we don't put as much money and time and training and resources into the intelligence component of finding how who these people are, what they're doing -- and, again, what does that require when they leave prison? Well, that's going to require profiling and monitoring. And I spoke about it a minute ago, the progressive left doesn't want to do that. So they know full well that there is no mechanism right now to track these people once they leave the facilities.

But one thing I found out about seven, eight months ago -- and, Tiffany, I don't know if you know this: There's a congressman in Tennessee, and I forget his name. I think maybe Fincher. I'm not sure if that's him. But he -- he had sponsored a bill -- I don't know if it's Corker. I think it's Fincher -- something. I'll find that for you.

He is sponsoring a bill to do something that I assumed was being done. And, boy, was I ignorant. And that is to vet clergy that come into prisons. Right now, imams that are coming into prisons who are allowed to speak confidentially with inmates, they have the same confidential privileges as an attorney, they're not vetted.

It doesn't matter if that imam preaches Islamic jihad, hellfire and brimstone, night and day, calls for death to America, death to infidels, they can walk into a prison and speak unmonitored, unrecorded, whether it be audio or video, to these prisoners. They're allowed to walk into that prison, radicalize and weaponize inmates. And think about inmates, they're already prone to violence. They already hate the government because the government incarcerated them. And they're pre-disposed to hate Americans that they've committed crimes upon.

And we don't have one mechanism in place to vet these people. On the federal level, on the state level, or at the local level. And I believe that law would only apply to federal prison, which would still leave all of the state prisons and all of the local jail facilities open and vulnerable to conversion.

And it really is so dangerous. And we're not hearing enough about this. I went back through archives, CNN never -- maybe they did. But I couldn't find -- let me preface this by saying, I couldn't find one CNN story on this, in-depth. I couldn't find a Fox News story on this.

I saw pieces on blogs touching on this. But I could not find an ABC story, an NBC News story, a CBS News story on this.

The mainstream media is ignoring this. And they have the intelligence. They're being advised by their contributors, their security, their intelligence -- contributors are telling them about this. They're not running the stories.

And it goes back to ideology, right? It goes back to the ideology of the radical Islamist and the people that they are taught.

When they're radicalized and weaponized, they're not just taught to hate people in general. They're taught to specifically hate Christians. And, Tiffany, you have family in the Middle East. I mean, you have experience with this.

TIFFANY: Yeah, my family survived Islamic persecution in Iraq. I mean, they fled. They were forced to be refugees. My father fought in the Israeli War of Independence in '48. So he fought them during a Polgram (phonetic) in Baghdad as a child and then again in '48 in Israel.

And what a lot of Westerners don't understand is that this is truly systemic. Even if a minuscule portion of the world Muslim population will actually pull the trigger and become terrorists, the greater number actually harbor these very radical ideas that are rooted in the Koran.

I mean, there are numerous Koranic verses and hadis (phonetic) that I could quote that talk about the subjugation and hatred for Jews -- and to a lesser extent Christians. But definitely Christians as well.

And this is systemic in Islam. There is a tribal mindset that the western world really grapples with and has a hard time understanding.

But people who come from the Islamic world like my family -- and be they Jews, Christian, Yazidi, anyone who is persecuted -- and there are obviously wonderful Muslims. I don't want to always have to add that qualifier. Of course, there are.

But by and large, there is a tribal mindset that is taught to hate and is taught to basically, you know, oppress and subjugate those who aren't like them.

JOHN: Well, and let me put this in perspective. Because you touched on an interesting point and a critical point, right? There are good people around the world -- no matter your faith, your orientation, your race, your creed.

And so let's be very, very generous here. There's 1.7 billion Muslims in the world. Let's say -- now, even the most progressive analysts will say, and only 1 percent will radicalize and potentially weaponize as terrorists.

Well, that's 17 million.

So let's you and I be a little more generous. Let's say half a percent. That's eight and a half million. No. Let's say a quarter percent.

4.25 million Muslims around the world, a quarter percent, where one-fourth of what the progressive analysts even will acknowledge.

That's 4.25 million terrorists. The combined strength of the United States military, all services, and the active law enforcement community, as we sit here today is about 3 million. They still outnumber us by 1.5 million. To me, that's scary. And that's a number you don't hear.

TIFFANY: Listen, even Pew research did extensive studies. I mean, we're talking about Muslims who want Sharia as the law of the land. This is in countries that aren't even as radical as Saudi Arabia. The majority want Sharia to be the law of the land. In Egypt, 85 percent support the executing of apostates. Those are infidels. Those are non-Muslims.

JOHN: Oh, yeah.

TIFFANY: Jordan, 82 percent. Palestinian territories, 66 percent. Those are being Islam --

JOHN: So we're being incredibly generous with our quarter percent number.

TIFFANY: Absolutely.

I mean, just because you won't put on the suicide vest yourself, doesn't mean that you don't support it emotionally and otherwise.

JOHN: Sure.

Even in our military, in our law enforcement community, for every man and woman in the field or on the street, there's a support network behind them. You can't exist without that.

It's terrifying. But, again, we talked about this pretty much throughout the show today. It all goes back to academia. It's what you learn and where you learn it.

And Harvard University -- Harvard University, right? That shining light. That beacon on the hill that everybody looks to and is guided by in academia, Harvard University is now assisting this.

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