20151115_wesun_update_on_paris_attacks_investigation.mp3?orgId=1&topicId=1124&d=222&p=10&story=456094087&t=progseg&e=456094024&seg=11&ft=nprml&f=456094087

The terrorist attacks in Paris on Friday could be an early harbinger of a new, more professional kind of terrorist attack leveled against the West.

In the past, al-Qaida depended on violent jihadis showing up in Pakistan or Yemen with a passport or visa that would allow them to return to home. The group would train them and send them back. Counter-terrorism officials are concerned that ISIS has taken that a step further by sending battle-hardened fighters to do their dirty work.

Al-Qaida, for example, had developed a six-week training program for potential terrorists. It included teaching recruits basic tradecraft and how to build a bomb. Once they graduated, al-Qaida would send them home. Invariably, something went wrong.

The young men and women either couldn't make the explosive work, or as in the case of Faisal Shahzad, the Times Square bomber, couldn't follow directions once they were home. Shahzad substituted ingredients in his car bomb and it failed to go off. Their lack of experience also often allowed authorities to discover them. When Nazibullah Zazi, a Denver man sent to bomb the New York subway system, couldn't make his explosive work, he contacted his handler for help. U.S. authorities intercepted that call.

Officials are now working under the assumption that the Paris attacks may have been perpetrated by men — and possibly a woman — who fought and trained in Syria. In other words, terrorists who were essentially professionals, instead of the amateurs that al-Qaida used to use.

U.S. officials have been watching changes in strategy from ISIS in recent months. They appear to be training their foreign fighters on the battlefield, in real-life situations, which makes them more successful terrorists later on.

Security in France has been tight ever since the attacks on the satirical magazine Charlie Hebdo in January. But that clearly wasn't enough. U.S. officials say they have a numbers problem: about 1,200 people have left France to go and fight in Syria with ISIS. According to counter-terrorism officials, some 200 of them have returned and folded themselves back into French society. Watching them 24 hours a day is untenable.

As a general matter, keeping someone under surveillance around the clock requires about a dozen people. The French police and intelligence services don't have the manpower to do that. So they are having to make educated guesses about who deserves their attention.

The two brothers behind the Charlie Hebdo attacks, Cherif and Said Kouachi, had been tracked by police for years. Authorities stopped following them six months before they gunned down the editorial board of the magazine, because they made the calculation that other people in France were more dangerous. It's a scenario that is replicating itself all over Europe; with over a thousand people on the continent who have traveled to Syria and returned, there is no practical way to keep tabs on them all.

In the U.S., the FBI has been tracking dozens of returnees from the battlefields of Syria and Iraq. FBI Director James Comey has said he believes the Bureau has a very good handle on those people. That doesn't mean the U.S. is immune to this sort of more professional attack — all the problems of professional fighters could be here — but the numbers make it much more manageable.

The U.S. is helping France look for other suspects and possible accomplices. French authorities found a car in the suburbs of Paris that was associated with one of the gunmen and they are now looking for a possible eighth assailant. They appear to know who they are looking for. They are also tracking how the attacks were financed, how the men brought AK-47s and suicide vests into Paris, and whether they have the Syrian connection that authorities fear makes it easier for ISIS to successfully attack.

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