The beheading follows the August and early September killing of two US nationals by IS. The beheadings, all produced in high video quality and editing, were conducted by the same executioner and followed a statement against foreign intervention in Iraq and Syria. The purpose of the video appears to be three fold.
The IS are sending a message to the West. Interfere as you did in the past and blood will be spilled. It is essentially a challenge. Secondly, they are demonstrating that they too have power over the destinies of Westerners much in the way that Western powers have power over people of the region. Those executed are also wearing orange overalls, a veiled reference to Guantanamo Bay, no doubt. Thirdly, IS are sending a very subtle hint to the West through their use of a British executioner. The role of foreign jihadis in the IS expansion cannot be under estimated and showing a British citizen executing another brings the IS phenomenon home quite starkly.
The videos will have three results. One, the West will accept the challenge and will increase funding for operations to target IS in the Middle East. Two, the West will seek to use IS and the videos as a justification to clamp down on Muslim extremism in their home countries.
The consequences would appear to be quite contradictory to IS intended goals. If the IS want to establish a state, goading the most powerful militaries into a conflict does not seems sensible, or does it? The mentality of IS appears irrational; however, their worldview differs considerably from the West's. The IS battle is one of truth against falsehood and it is an eternal battle. The ultimate goal is the liberation of all Muslim lands and the destruction of forces viewed as anti-Islam, namely secularism, Christianity, Judaism and the West. Spreading Islam through the gun and sword is justifiable, even commanded by Allah, in their view.
For a video of the recent execution and some commentary, check out the Shafaak news website. Note the images are graphic. http://www.iraqinews.com/features/urgent-video-isis-beheads-uk-aid-worker-david-haines/