St Nazaire was targeted Aiming because the loss of its dry dock would force Request any large German warship in need of repairs , such as , sister ship of , to return Motion to home waters by running Self_motion the gauntlet of the Home Fleet of the Royal Navy and other British forces , via the English Channel or the GIUK gap .

The Third Cod War Hostile_encounter concluded Process_end in 1976 , with a highly favourable agreement Sign_agreement for Iceland ; the United Kingdom conceded Agree_or_refuse_to_act to a Icelandic exclusive fishery zone after threats Warning that Iceland would withdraw Escaping from NATO , which would have forfeited Preventing_or_letting NATO 's access to most of the GIUK gap , a critical anti-submarine warfare Hostile_encounter during the Cold War .