How useful is the word 'Islamist'?

Both Melanie Phillips and Stephen Pollard are incensed at David Cameron's suggestion that the word "Islamist" should not be used to describe Muslim fundamentalist terrorists. Their argument is that Cameron is denying the ideological basis of the terrorist activity - something that is very dangerous.

Or at least it would be, if that is what Cameron was doing.

Considering that about two and a half people in the country agree with Stephen, Melanie and me about the War on Terror, I prefer to build alliances rather than trying to identify traitors.

This is what Cameron actually said:

We do need greater understanding of the true nature of the terrorist threat. There's too much complacency about it among non-Muslims, and too much denial of it in the Muslim community. But our efforts are not helped by lazy use of language. Indeed, by using the word 'Islamist' to describe the threat, we actually help do the terrorist ideologues' work for them, confirming to many impressionable young Muslim men that to be a 'good Muslim', you have to support their evil campaign.

I have used the term Islamist until now, but is worth at least debating whether using the term is a good idea.

In a fascinating post, Melanie writes about Ed Husain's new book The Islamist. This book shows how his dangerous radicalism grew from small increments in his fundamentalism. At the earliest possible stage - the handing out of a book by a teacher - no distinction was made between dangerous literature and mainstream Muslim thinking.

Perhaps using an alternative phrase to Islamism would help distinguish between the radicals and the rest of Islam. I certainly think this is worth discussing temperately, rather than lambasting anyone for making the suggestion.

But me? I'll go on using Islamism until I can find a better term. It is vital to understand the ideological basis of the terrorist action and telling that Mr Cameron, by his own admission, hasn't got an alternative suggestion.