you reckon?
I think there is still more to come. If you consider how totally incompatible western liberalism and islamic orthodoxy are I think we ain't see nothing. There are entire communities living in poverty in East London who have zero connection with the UK mainstream or any kinds of liberal ideas and who are fertile ground for the militants. Living in West Ealing, on the other side of town, I also met a few Muslims who were openly misogynistic, hated black people, gay people, liberal people, in fact anything English. The majority won't act on it but for some there is a strain of hatred there lurking beneath the surface, just waiting to explode.
I would feel local intelligence has those militants under surveillance. Unlike the IRA, they stand out more for obvious reasons and dont integrate with normal society.
The Muslims that you refer to are real, but they need a leader of stature to incite them if they were to become militant. Once again I would expect intelligence to have strong grasp of the situation.