'Backbone' was a British unrealised contingency plan for an amphibious landing to take the Tangier and Ceuta area of Spanish Morocco during 'Torch' (late 1942).

Never fully formulated, the scheme was abandoned as its implementation would have added additional logistic and strategic complexity to no real positive purpose, and would also have heightened the possibility of a Spanish entry into the war on the side of the Axis powers and, as a result of the latter, a renewed Axis threat to Gibraltar.

A concomitant undertaking was schemed by the British as 'Backbone II', to which some consideration was given as a US counter to any Spanish reaction to the implementation of 'Backbone' by the seizure of the area of Spain adjacent to Gibraltar late in 1942 or early in 1943. This operation was rendered superfluous by the abandonment of 'Backbone'.