Strategy Page explains how increasing sophistication on the part of the al Qaeda/Taliban forces has been allowing them to select targets of opportunity through things like Facebook posts and cell phone traffic:
The U.S. Army is warning its troops to be careful what they post to on social networking sites (like Facebook). When they post photos of themselves they often reveal militarily useful information. This was discovered in Iraq, where a lot of tech savvy people working with terrorists were able to compile information from what troops posted. This sometimes led to attacks, and this was discovered from interrogating captured terrorists and captured documents and computer data. The background of pictures often indicated targets for the terrorists, or details of base defenses and American tactics. Islamic terrorists have been quick to use the Internet and other modern technology to plan and carry out their attacks.
Some of this technology can be very dangerous, like the geo-locating capability of many smart phones (which include GPS receivers and location data that hackers can obtain.) Troops in combat zones are ordered to turn geo-locating off while in areas where the enemy could use it. Even without geo-locating turned on, cell phone use can provide militarily useful information. This goes back to a century old practice called traffic analysis. This has been used with great success against terrorists in Iraq, Afghanistan and elsewhere, but it can be used against the troops.
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Al Qaeda was long suspected of knowing how to manipulate message traffic in order to deceive our traffic analysis methods. This was rarely the case, but this form of deception has been used in the past with success. For example, when the June 6, 1944 D-Day invasion of France was being planned, a fake army group headquarters was set up in England. Actually, this “army group” consisted largely of a lot of radio and telegraph operators sending a large number of messages that would be normal if the “army group” were preparing for an invasion of France, in an area other than where the actual invasion was going to take place. The deception worked. German traffic analysis experts were fooled and the Germans believed the actual invasion at Normandy was just a feint, a move to get the Germans to send their reinforcements to Normandy rather than were the fake “army group” was going to invade.
Intelligence agencies have to be constantly on the guard for al Qaeda, or any other terrorist group, using this kind of deception. It has happened in a few instances, so a larger-scale attempt is not out of the question.
