More nukes for UK? On what nuclear deterrent theological grounds?

Whoever in the UK Ministry of Defence came up with the advice to increase Britain's nuclear warhead numbers from 180 to 260 as part of the comprehensive review of security and defence strategy published yesterday needs to explain the rationale for this rise. Personally, having written about nuclear weapons and nuclear deterrence, among other things, for the last 30 years or so I simply do not understand how the meaning of "minimum credible deterrence" which has always been the UK government's posture ever since we had nuclear weapons, has in any way changed. Boris Johnson and co said it was necessary to increase the number of nuclear warheads available because of changing circumstances in the world and the pursuit of larger nuclear arsenals by certain countries, ie China. I'm sorry but that doesn't wash, not if you have a proper understanding of what minimum credible deterrence means. In the simplest terms, the theology of nuclear deterrence is that a prospective enemy will think twice before risking a weapons of mass destruction attack on the UK because they realise that if they do so the UK prime minister will order a nuclear retaliation, sufficient in size and devastation to cause totally unacceptable and long-lasting destruction. The Cold War concept of mutual assured destruction still holds today and, hopefully, always will. But does that concept become stronger and more lethal and add deterrent value if the UK increases its stockpile from 180 to 260. In other words, is more better than less? If China, and let's say North Korea and Iran (please God not) build large arsenals of nuclear weapons, outstripping the UK's stockpile, does that place us as a country in more or less danger of annihilation if we have 260 nuclear warheads or if we have 180 warheads? In pure deterrent theology terms it should make no difference at all. The only rationale I can think of is that if a Royal Navy ballistic-missile submarine is on patrol and nuclear war breaks out, the prime minister of the day can order the sub commander to fire, say, four extra Trident missiles, knowing that with the additional 80 warheads in the total arsenal the Royal Navy will be able to carry on firing nuclear ballistic missiles at the enemy for longer and over a wider range of territory. But to adopt that argument is to encourage madness. One Trident missile with its multiple warheads would do such huge damage to a city that, unless the UK wants to destroy a whole country, east, west, north and south, there would never be a situation in which the UK prime minister would be eternally grateful and thankful that he or she has 260 nuclear warheads, rather than 180, to launch at the enemy. By then the world would have come to an end anyway. So no time or point for any future prime minister to give himself/herself a pat on the back. This is the reality of nuclear war. Once the button is pushed, deterrence has failed. So in my opinion there is no reasonable theological argument to justify increasing the UK's nuclear warhead stockpile from 180, which previously the government had planned to reduce to, to 260. And that's before even venturing down the morality path. The UK is signed up to the Nuclear Non-Proliferation Treaty which means it must do everything in its power to prevent the spread of nuclear weapons in other countries and as a quid pro quo, for nuclear powers to reduce their stocks to demonstrate a willingness, one day, to rid the world of all nuclear weapons. Ronald Reagan had that dream years ago! There is no question that China plans to expand its nuclear capability over the next decade. But is that really why the UK government has decided it is imperative to increase the number of nukes by 40 per cent? It's a false argument and it worries me if there isn't anyone of sufficient experience and knowledge to have made this point during the strategic review. If there was, he or she, must have been shouted down. I wonder what Sir Michael Quinlan, probably Britain's greatest nuclear strategist and deterrent theologian, would have said if he was still alive today. The former permanent under secretary at the MoD sadly died in 2009. His words of wisdom might have weighed against the decision announced yesterday which, summed up crudely, seemed to be about "more nukes and fewer soldiers".