Sir James Eric Sydney Cable KCVO CMG (15 November 1920 – 27 September 2001) was a British diplomat and naval strategic thinker.

Following officer training he was commissioned as a second lieutenant in the Royal Corps of Signals on 18 October 1942,[2] and rose to the rank of major before joining the Diplomatic Service in 1947,[1] his appointment was confirmed with effect from 18 November 1948,[3] although he did not relinquish his army commission until 28 October 1953, when he was granted the honorary rank of major.

[5] He subsequently served in the Middle-East and as head of the Foreign Office South-East Asia Department for two years.

[1] Cable became the head of the FCO's Planning Staff from 1971 to 1975, and was then briefly Assistant Under-Secretary of State, before returning to Helsinki as Ambassador from 1 October 1975 until his retirement in 1980.

[1] Cable defined gunboat diplomacy as "the use or threat of limited naval force, otherwise than as an act of war, in order to secure advantage or to avert loss, either in the furtherance of an international dispute or else against foreign nationals within the territory or the jurisdiction of their own state".