The current threat is not from traditional armies but from a range of opponents as varied as individual terrorists to warlords!
It would seem that the best solution is to apply ecconomic pressure on them and their supporters. Trident (as I understand it) is a complete missile system using Nuclear warheads. I fail to see how this system could be used with any degree of legalitty or indeed usefullness!
The concept of Trident is however different in that it includes R+D.
This is a whole new ball game! Who knows what the spinoffs from this will be?
HOTOL? ..... a scramjet missile just big enough to carry a nuclear payload at mach 20.
Tactical Battlefield Nukes ....(1) If your enemy is clustered in one area Kablamm! Problem solved
                                           (2) EMP your enemy and they are defensless for a while
                                           (3) .... Small nuke in a mountain pass and the radiation has blocked the whole area!
Nitrigen bomb ..... Enough short wave radiation to sterilise an area and allow the troops to occupy all that infrastructure.
I do not have all the answers but I do have some ideas and they all point to us keeping the nukes in one form or another! {8¬O)