Delivering a fatal blow to terrorist leaders in an attempt to kill off the entire groups rarely has the desired effect and amounts to little more than militaristic box-ticking, writes Arie W Kruglanski

The head of the extremist Islamic State group has said it will fight to the last man.

As our own history shows, chaos — or as the victors might call it, revolutionary restructuring and reeducation, often fills the vacuum left by a retreating imperial force.

The leader of radical Sunni fighters who have made rapid military advances in Iraq is the rising star of global jihad, driven, Islamist fighters say, by an unbending determination to fight for and establish a hardline Islamic state.

AT LEAST 118 Shi’ite pilgrims were slaughtered in attacks across Iraq yesterday, sparking fears of reprisals that could frustrate efforts by Iraqi and US forces to quell sectarian violence.