If we thought that successfully monitoring and catching all terrorists before they attack is an easy job for any country, especially one like France where human rights laws are important, then we were wrong.
France is not Russia or Saudi Arabia where you can stop anyone anywhere, without a court order (and even they have not been able to stop all terror attacks on their soil). So to catch the terrorists before they strike, you must first monitor them.
Do you know how much resources are needed to monitor just one person for 24 hours?
The answer is at least 18.
According to Dame Stella, the former head of MI5 (UK domestic intel agency):
To keep a constant watch on just one of those people, you would need a team of at least six surveillance operatives, Dame Stella says. But of course they couldn’t work 24 hours a day, so you would need three teams of six.
Thats the number of people who are directly involved. Then you also need a backup team. So the number of people you need keeps rising.
Now lets just imagine you have 2000 people on your watch list. Some are former ISIS people who have returned, some are local jihadis. So how many people in total would you need to keep an eye on them 24 hours a day? According to the BBC, that number would approximately be:
50,000 full-time spies doing nothing but following suspected terrorists.
Now lets put that into perspective:
Who on earth can do that?
Add to that the challenge of terrorists using a vast array of application which have end to end encryption. For example, according to the Belgians, ISIS has been using Playstation 4 to communicate with its terrorists. Meanwhile according to a new book, the Mossad recently discovered terrorists using porn sites and ebay to transfer encrypted messages. Now just think how many things ae listed on ebay and how may porn pages there are on the internet.
This is why security agencies have to prioritize, and focus on some targets, because they can’t keep an eye on all of them. And this is why sometimes, some of the criminals slip through the net, like last night in Paris.