US citizens are required to be wary that terrorist may launch attacks without warning in advance. The US State Department website recalled the attack at a Christmas market in Berlin, Germany, in December last year, killing 12 people and another attack at a nightclub in Istanbul, Turkey on New Year's Eve killing 39 people. Recent terrorist attacks in Britain, Finland, France, Russia, Spain and Sweden have shown that both the Al-Qaeda and IS terrorist organizations have the potential to cause out attacks during holiday season.
