This is an interesting point. Has American pressure got anything to do with the Labour Party's recent change of direction on Islamism?
Here's one reason to think this might be an issue, from the C.I.A.'s website - a U.S. national Intelligence Council document. Quote:
A New Caliphate provides an example of how a global movement fueled by radical religious identity politics could constitute a challenge to Western norms and values as the foundation of the global system.
Hat tip - Sir Percy.