I don't think the Machiavel gambit could be accepted by a large enough section of both British and Itish leadership.
I think it hangs on the british - but there I agree they are not willing to do what it takes.
Im hungarian. Hungary and hungarians during the Habsburg rule were very often referred to as rebellious - and with good reason. We received the Machiavellian treatment twice - and it worked in both cases. Especially telling is the story of our former communist dictator János Kádár. He has betrayed the 1956 revolution and resided ower a very brutal reprisal. In '57 and '58 I think you wouldnt have found anyone more hated in the country. By the late 60's its speculated that he would have won even on a free election - which is an incredible change of attitudes in just a decade. So however inhuman and morally problematic it is I do believe that it works. I think it would have worked on the irish as well.