ALEX WITT: This morning, the six New Jersey men accused of plotting an assault on a military base are in custody without bail but as details about their background emerge, some are wondering why the law didn't crack down on them long ago. Indeed, the three brothers allegedly involved in this plot were living in the U.S. illegally and had many run-ins with the police over the years. In all, their driving privileges were suspended -- you're not going to believe this -- 54 times in less than a decade. And in 2000, one of the brothers plead guilty to possession of marijuana yet none of this triggered immigration background checks. With me now, Steve Emerson, terrorism analyst and author of Jihad Incorporated: A Guide to Militant Islam in the U.S. Steve, good morning to you.

STEVEN EMERSON: Good morning, Alex.

WITT: My question here: here: local police, is that who's at fault or is there a deeper problem that makes it easier for illegal immigrants to avoid detection?

EMERSON: No, it's not lot police fault, it's quote the system's fault and that's the large system with a capital s, because there isn't a database that basically interfaces with one another that comprehensive and covers all of these local arrests and also covers the immigration violations. Sort of like social security. There's no massive database that covers all social security violations.

WITT: In your analysis, how common is this kind of thing? We've got a potential terror suspect, multiple -- I'm just flabbergasted, 54 times having driving privileges suspended over less than a decade. But you've got all these run-ins with the law. The system prevents authorities from ever connecting the dots.

EMERSON: It happened on 9/11 too. Mohammed Atta was stopped I think for a violation with his airplane on a runway right several weeks before the 9/11 plot was utilized. And here he had violated one of the visas that he came in on. It should have been uncovered easily and the plot could have been disrupted. Again, the systems didn't talk to one another.

WITT: As you know, Steve, Congress is fighting over immigration reform. Where do you think terrorism fits into the debate on immigration?

EMERSON: Well, I think it fits in largely. Look, there's no doubt that the mass amount of illegal immigrants are here for economic reasons. But you have a smaller number that are here for a nefarious purpose. And the fact is, even those that may have come here, like these guys, who came here from Albania or from Turkey for perhaps economic reasons, they turned and they turned up hating the United States and carrying out -- trying to carry out a terrorist attack. So the -- the terrorist question has to enter into the immigration debate.

WITT: So these guys, do they fit the expected profile or do they represent a new kind of threat?

EMERSON: Well, the only -- quote -- "profile matrix" that they fit is the fact that they come from a Muslim country. And that's -- some of them had white European looks, those from, you know, Macedonia. But they did come from Albania. And the fact is, that does reconfirm the notion that those coming from Muslim countries need special scrutiny. It's not pleasant, it's not especially comfortable for others innocent that come from Muslim countries but that in large part is 99% responsible for those who carry out terrorist attacks.

WITT: You know, look, you've written the book, "A guide to militant Islam in the U.S.," So I guess you're the one to ask, do you have any idea how many guys like this are out there in the U.S.?

EMERSON: Well, you know, Alex, one of the problems is it's not just guys out there like this, it's guys who are out there who could become like this. Remember, these guys weren't like these two years ago. They were -- or three years ago. They were part of the American dream. They became radicalized here. And, therefore, we're talking about lots of ticking time bombs that we don't even know that they're ticking now.

WITT: Which ones do you fear more, Steve, the ones that come over here with a purpose or the ones that change their minds once they've gotten here?

EMERSON: Well, that's a good question. Obviously the ones that come over here with a purpose are definitely known to be ticking and there's an ability to track them since we know they're coming in from the outside. And there are wiretaps and there are money transfers you can follow. The ones that are already here, it's very difficult to track them because they're here already and you don't know if there's any money transfers because they're self-contained and they're self-activated.

WITT: You know, Steve, a clerk at circuit city found this guy -- found these guys. Is this just luck?

EMERSON: It's -- it is -- yeah, it is damn good luck, I must tell you. Because clerks at circuit city or any other store automatically dub video. And generally speaking, they don't even look at what they're dubbing because they do so many of them. And so he paid attention. Something must have caught his eye and he heard something. And he decided to look further. And he represented -- and he presented this to the F.B.I. Thank god he did this because -- now, look, under other circumstances in the previous five years, like that waitress down in a southern state that called authorities because she saw three, you know, people in the restaurant she thought were suspicious and they were driving down alligator alley? She was subjected to a lot of taunts, a lot of death threats, she was called a racist. She did the right thing. She thought they were possibly suspicious. So it's a judgment call. It's the same thing with those passengers on the flight carrying the imams out of Minnesota. You know, American civilians, American popular civilians have to report what they believe are legitimate security threats. It doesn't mean that they always pan out but in this case, it did pan out.

WITT: Yeah, on. Steve Emerson, more to come with you. Don't go too far, my friend. Thanks.

EMERSON: Sure.