The closeness of Anglo-American military and intelligence ties, driven by the cold war, became a defining feature of British foreign policy and a source of tension between Britain and France, which led de Gaulle twice to veto British membership of the then European Economic Community, on the grounds of Britain's irremediable Atlanticism.

ECONOMIST: Britain and the cold war

But the intervening years and the end of the cold war do not appear to have changed the nature of the Anglo-American intelligence relationship.

ECONOMIST: Those perfidious Anglo spies

During the Cold War and events of 1991-2003 in Iraq the problem of gaining sound intelligence on chemical weapons was encountered over and over again.

BBC: Could US remove Syria chemical weapons?