Stratfor: "European Terror Threat Overstated".
Although it seems to have been overlooked by the media, it is hard not to conclude that Islamist acts of terror are not usually preceded by specific threats, and Islamist threats are not usually followed by attacks. This is basic psychological warfare, and usually works well – authorities in target states must not ignore the threats, and defending against the threat of attack for an indeterminate time frame is costly as well as stressful.