A video address by the chief Islamic State (IS) spokesman Muhammad al-Adnani calling for members to kill civilians and soldiers in countries including Australia has divided opinion among terrorism experts. This video has led to a discussion worldwide focusing on the question: what are the implications of contributing to the fight against IS for the countries who pledged their support?

In terms of terrorist threat levels, there are two main consequences: the threat increases for citizens abroad and for citizens at home for those countries that joined the coalition. First, there is an increased threat for citizens who currently are in or near the region controlled by IS in Iraq and Syria. However, the threat is not confined to that area. Citizens who are travelling or working in countries where terrorist groups related to IS are active are also at risk – as shown by the beheading of a French tourist by an Algerian group linked to IS last week. A Philippine group, Abu Sayyaf, has threatened to kill two Germans if Germany does not pull out of the coalition against IS. This group allegedly also holds a Dutch citizen, Ewold Horn, who has been kidnapped in 2012.

Second, the pledge to fight IS has led to increased terrorism threat levels domestically. The Netherlands received a wakeup call in the form of a video message of a Dutch foreign fighter who called his brothers to arms after a bombing campaign had left an alleged hideout for Al-Nusrah fighters in Iraq in ruins. In the video message, he called on his brothers to retaliate against the Dutch government The Netherlands. In response, the Dutch Department of Defense ordered military personnel not to wear their uniforms in public transport anymore because they might provide an ‘easy target’.

All in all, the fight against IS has implications for the countries who participate in it both on foreign soil and domestically. However, the end goal of this fight is to diminish the threat posed by IS altogether and the consequences have to be viewed within that broader perspective. The possibility of an attack is realistic, yet as long as there is no concrete evidence that an attack is about to happen there is no reason to panic or behave differently based on fear. For the time begin, therefore, most terrorism experts agree that civilians should ‘Keep calm and carry on’.

The video below shows the Dutch foreign fighter urging for retaliation against the Netherlands. [In Dutch]