The title of this article carries an implicit presumption that British and French nuclear weapons ought to have a place in arms control. Due to the way in which arms control negotiations have evolved-especially with the distinctly artificial separation of 'strategic' weapons from 'intermediate' weapons at Geneva-it is not obvious where that place should be. This is a proper subject for debate. But what the British and French governments cannot any longer do without laying themselves open to charges of gross inconsistency and obstructionism is to argue that American and Soviet nuclear weapons should be constrained through arms control while British and French weapons of the same general kind are not. To begin at the conclusion, Britain and France have no grounds, either in equity or in politics, for standing aside from taking proportional reductions if there are reductions in the nuclear weapons of the superpowers. This raises difficult questions for nuclear forces which their owners state (and believe) are 'minimum deterrent forces'. This article will present the argument that these forces seem to be developing to a point well beyond that which was previously regarded as the minimum deterrent level, and that it is not clear why it should be necessary, greatly to alter the retributive capacity of 'minimum deterrent forces' simply because the potential opponent increases his forces. There is a very respectable argument in deterrence theology for taking whatever steps are necessary to ensure the survivability of these minimum deterrent forces or 'weapons of last resort' in the face of a changing threat, but unacceptable damage remains unacceptable damage, in the absence of effective defences. If this calculus was initially based on the capacity to inflict a certain degree of pain on an opponent in retaliation, why should it now be necessary to increase the destructive potential of the deterrent force? In terms of practical politics, the subject of the planned expansion of the British and French forces could be introduced alongside the bilateral US-Soviet strategic arms negotiations, either by offering force increases lower than those planned if the Soviet Union reduces its forces threatening Britain and France, or, if the new weapons are already deployed here, reducing them back to consistency with earlier definitions of what constituted a minimum. If the time were ever to arrive when both superpowers had reduced so dramatically that reductions below the minimum were demanded of Britain and France, it would be a much safer world and they might be able to afford to do so. It is well known why the essential purpose of British and French nuclear forces differs from the superpowrers' strategic or intermediate nuclear forces; yet they share many of the latter's characteristics. They are basically ballistic missiles carried in nuclear-powered submarines-and these are systems genlerally acknowledged in SALT and START to be 'strategic' regardless of missile range and so 'central' systems for the superpowers. Whatever differences one can point to in technrical