If it was just 'Islamic State' I wouldn't worry because they are 'over there'.
However, it is the potential 'enemy within' that causes me greater concern.
The peaceful majority of Muslims in this country, indeed, worldwide, are irrelevant. It is the minority that seek to impose sharia upon us that worry me.
The recent deaths in Sydney, Paris and Copenhagen are bad enough but it is the reaction to them that shows how what was once considered the 'traditional West' is losing this battle.
Halal food in Pizza Express and Subway; pork withdrawn from school meals; segregated swimming sessions - these are but the minor symptoms of a loss of identity and courage.
It's quite simple - if you want the freedom to practise your religion, that comes with the freedom for others to criticise, ridicule, mock, insult and vilify said religion. Otherwise, go elsewhere.