Well, if we retire the GR4 then there is no hope of the cheaper alternative of putting the Nuke deterrent back with the RAF!! We could, of course, go down the cheaper route of the nuke tipped Tomahawk launched from the hunter/killer subs and ditch the SSBN beasts??
Or we could just stop trying to be the world police and withdraw into international obscurity and lead a sheltered life such as Sweden et al. I mean, what good has our crap foreign policy done us anyway over the past 30 years??
Great Britain - maybe 100 years ago - now Broke Britain maybe more apt...(sigh)