ISIS supporters threaten fresh attacks on the West in chilling propaganda posters showing a suicide bomber in New York and a burning Palace of Westminster in London

Raffaello Pantucci of RUSI, a defence think tank, warned earlier this year that the territorial defeat of ISIS was not the end and that and the 'biggest danger' was stepping back. 'I think the danger is that we end up doing what happened in Iraq in 2009 - we just kind of left and left the whole place to its own devices,' he said. 'And essentially it didn't get better, the governance continued to be a problem and that is how the environment was created for the group to grow in to. I think the danger is that we end up doing what happened in Iraq in 2009 - we just kind of left and left the whole place to its own devices,' he said. 'And essentially it didn't get better, the governance continued to be a problem and that is how the environment was created for the group to grow in to.'