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Expert: Terror Plot Similar to 1994 Airline Attack

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Expert: Terror Plot Similar to 1994 Airline Attack


Expert: Terror Plot Similar to 1994 Airline Attack

Expert: Terror Plot Similar to 1994 Airline Attack

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Terrorism expert Daniel Benjamin, a senior fellow at the Center for Strategic and International Studies, tells Renee Montagne that the alleged terror plot in the U.K. is very similar to a bombing that took place on a Philippine airliner in 1994, killing one person.


Joining us now is terrorism expert Daniel Benjamin. He's a senior fellow at the Center for Strategic and International Studies.

Good morning.

Mr. DANIEL BENJAMIN (Center for Strategic and International Studies): Good morning.

MONTAGNE: The government is taking some unprecedented steps, as we've just heard, including the alert level to red for commercial flights to Britain and the U.S. Sounds very significant. What - how do you see it?

Mr. BENJAMIN: Well, it's unquestionably very significant. Obviously, we're dealing with very little information at the moment. But the conspiracy, I mean what we've learned, suggests that this is actually very much like one that was undertaken by Ramzi Yousef and his relative, the famous Khalid Sheikh Mohammed, in the 1994 and 1995 period.

Ramzi Yousef invented, as it were, a kind of an explosive device that used a liquid and he tried it out on a Japanese - on a - well, on a Philippine airliner - that - and he killed a Japanese businessman. They were going to blow up 12 planes in flight over the Pacific. This plot was called Manila Air and also Bojinka. And it appears that this is a replay of that.

This caused an enormous disruption all over the Pacific Rim, and the same sorts of security measures were taken then, all liquids being taken away from passengers. I think the only exception was baby formula at that point.

MONTAGNE: Right. As was the case actually today, with the baby formula. But just a quick - liquid - which seems to be a very easy thing to get on a plane, sort of innocuous looking - what exactly would a liquid bomb be? What would happen? What concoction would be made?

Mr. BENJAMIN: The material that it's believed Ramzi Yousef was using is something called triacetone triperoxide, TATP. And the reason that it had not been used before - and he was also using nitroglycerin - is that it's very volatile and it can go off when you don't want it to. But it can - a small amount can easily put a hole in an airplane and cause a disaster.

And it is not detectable by the standard measures that are used at airplanes - at least it certainly wasn't at that time. And I don't think anything has been done to be able to detect it now. The usual scanners scan for solids and for a particular density associated with explosives. So that, I think, is why we're seeing the measures we are.

MONTAGNE: So do you think this threat, as it's been described, bears al-Qaida hallmarks?

Mr. BENJAMIN: Well, if you're talking about multiple more or less simultaneous attacks, especially on aircraft, absolutely. And this has been an interest of jihadist terrorist now for quite some time. Whether this was ordered up by bin Laden from the border region of Pakistan is much harder to say. But given the sort of nature of the threat right now, which is a lot of dispersed cells - many of them homegrown or self-starters, as we call them - it would be inspired by the jihadist ideology but not necessarily ordered by bin Laden himself.

MONTAGNE: Why would a terrorist plot focus on aviation again when security at the airports is so strict?

Mr. BENJAMIN: Well, several reasons. First of all, this - the jihadist terrorists do like to come back to foiled plots. Remember, Ramzi Yousef tried to blow up the World Trade Center in 1993, and of course they came back to it in 2001. Aviation has a peculiar horror to it, or an aviation attack. It's spectacular, it causes mass casualties and an awful lot of follow-on disruption that can really cause enormous damage to the economy.

So you know, really, for as long as there's been - well, since it - for a long time, there's been an awful lot of terrorism associated with aviation. And that link, I think, is well understood...

MONTAGNE: Mr. Benjamin...

Mr. BENJAMIN: the terrorists.

MONTAGNE: ...just briefly before - we have to go in just a couple of seconds. But does this reaction today, this - these arrests - suggest that this country is or Britain is better able to deal with plots like this?

Mr. BENJAMIN: Well, I think the British have done a very good job. I don't know that they're better able than we are, but they've certainly done very good work over the last - well, five or 10 years already.

MONTAGNE: Thank you very much.

Mr. BENJAMIN: My pleasure.

MONTAGNE: Daniel Benjamin is a senior fellow at the Center for Strategic and International Studies and author of the book, The Age of Sacred Terror.

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Primer: Why Liquid Explosives?

The alleged plot to blow up airliners over the Atlantic involved the use of liquid explosives, according to officials in the United Kingdom and the United States. Authorities suggest that the plotters planned to carry explosive ingredients aboard the aircraft in hand luggage — perhaps in cosmetics containers or beverage bottles — and detonate them. Here, a primer on liquid explosives.

How do liquid explosives work?

This type of explosive is simply a chemical compound that in liquid form is relatively unstable. A physical, chemical, or electrical jolt causes it to explode, usually producing a fair amount of heat, light and a destructive shock wave (a very rapid change in air or water pressure). Like solid explosives, liquid explosives vary in power, depending on their recipe and how they are packed into a container.

Why would terrorists want to use liquid explosives?

Security screeners have gotten much better at detecting solid explosives, while liquid explosives have proven much harder to detect. In addition, liquid explosives can be made from fairly common ingredients, including substances typically found in your garage or under your sink. Finally, a terrorist could assemble an explosive from components carried aboard a plane in separate containers or by different people — making it even harder for screeners to spot. One person could carry ingredient A on to the plane, another ingredient B, and then they could be combined.

Do liquid explosives have disadvantages?

Like many homemade explosives, they can be very volatile. Some can be set off by a stray spark, a change in temperature, exposure to sunlight, or even an accidental bump. For instance, the liquid nitroglycerin — made famous by Alfred Nobel, the inventor of dynamite and father of the Nobel Prize — is notoriously unstable. It can be set off by an accidental jolt. In fact, Nobel's brother died when a dynamite factory exploded. That's why the invention of more stable explosives, like sticks of TNT, was important. TNT typically needs to be ignited with a powerful blasting cap; it can even be melted safely.

Terrorists have tried several times in the past to blow up airliners with liquid explosives...

The U.S. government has focused on the threat of liquid explosives since at least 1995. That's when they learned about a plot in the Philippines to plant bombs on 11 airliners bound for the United States. The plotters apparently wanted to use liquid nitroglycerin. They planned to smuggle it aboard in bottles made for contact lens solution. But the plan came apart when there was a fire in the apartment where the bombs were being made. (A test run for that plot, a plane bound for Tokyo, resulted in the detonation of a liquid explosive in-air. One person was killed, and pilots were able to land the plane.)

Experts believe that terrorists have since moved on to use the type of explosives previously described, where the components are carried separately and then mixed at the site, to reduce their instability.

How hard is it to screen for liquid explosives?

They're a real threat to airlines. Currently security agencies have no test for liquid explosives. Technology is in the works, and several devices have been tested in airports. One kind uses microwaves to distinguish safe, water-based liquids (like coffee or soda) from solvents and other dangerous chemicals used in explosives. But this device can’t see through metal containers. Another kind of device sends laser light through clear glass or plastic. The light bounces back with a scatter signature that can be compared to a database of worrisome liquids. But this technology can’t see through opaque containers.

Why aren't some of these devices already installed in airports?

Experts have known for years that screening liquids is a weak spot in airport security, but other needs have taken priority. For example, one government report said that research and development was recently delayed when the Transportation Security Administration had to transfer funds away from R&D to other expenses, like personnel costs for screeners.

With reporting by NPR's Nell Boyce and Jon Hamilton.