How many weeks' holiday a year are there? leo pharma revenue 2016 In fact this assault is different to most that have gone before. Al-Shabaab came prepared for a long siege as opposed to a short sharp bloody attack. It seems their goal was to take control of an easily-defendable position with hostages to buy themselves the time to stage a propaganda coup. In a normal siege those surrounded are prisoners, ringed by security and only able to speak to those in authority. This group came prepared to wage propaganda war, continually tweeting via Twitter all throughout the siege to its supporters worldwide. It is the first known use of this social media in this way by terrorists.