What the authors are really saying, against the republicans, is that there is a case for reform. Whether the long term interests of the British ruling class include a final withdrawal from Ireland is more questionable. What is remarkable about their analysis is their sympathy with a Unionism now forced to accept at least symbolic recognition of Irish nationalism in the North. This is a recipe for sectarian confrontation. It seems foolish at least, not to allow for a greater expression of the relatively secular and modernizing aspects of the Unionist tradition.
Equal rights is deem sectarian and bigotry is labelled as secular.
An unstated alternative to the Bew and Patterson analysis is the idea that the northern Ireland state is simply irreformable. In practice the British state has not improved matters as regarding religious discrimination and employment as even the government's own studies admit. The six counties of Northern Ireland are the product of a partial victory against imperialism and the debilitating civil war within the nationalist camp which followed. On the contrary, this would seems to be a case of ruling class lucidity and is certainly more realistic than treating the Northern Ireland state in isolation. As we saw above, they suggest an expansion of the public sector and a concerted attack on structural religious inequity.