In a globalised, increasingly multi-polar world, the ‘special relationship’ between the US and UK might be expected to diminish, as twenty-first century reality supersedes Cold War imperatives. Nothing of the sort, it seems, when it comes to nuclear weapons.

In 1958 the US and UK signed the ‘Agreement between the UK and the USA for cooperation in the Uses of Atomic Energy for Mutual Defence Purposes’. Also referred to as the Mutual Defence Agreement (MDA), the treaty established a modus operandi between both countries to exchange classified information to develop their respective nuclear weapon systems. Originally, the MDA prohibited the transfer of nuclear weapons, but an amendment in 1959 allowed for the transfer of nuclear materials and equipment between both countries. This amendment is extended through a renewal of the treaty every ten years, most recently in 2004. Continue reading →