Bastion (naval)

A bastion in naval strategy is a heavily defended area of water in which friendly naval forces can operate safely. Typically, that area will be partially enclosed by friendly shoreline, defended by naval mines, monitored by sensors, and heavily patrolled by surface, submarine, and air forces.

The bastion became an important strategy for the ballistic missile submarine fleets of the Soviet Union during the Cold War. The Barents Sea was made a bastion for the Soviet Red Banner Northern Fleet, and the Sea of Okhotsk for the Soviet Pacific Fleet, both of which remain important to the Russian Northern Fleet and the Russian Pacific Fleet.

The Soviet Union had (and, even more so, Russia now has) limited access to the world's oceans: her northern coast is ice-bound at least the majority of the year, and access to the Atlantic requires transiting the GIUK gap; much of her eastern coast is also ice-bound and requires moderately close approaches to either Alaska or Japan; travel from her southern ports involves transiting first the Bosphorus and Dardanelles, and then either the Strait of Gibraltar or the Suez Canal.

The Soviet Navy originally attempted to directly contest with the navies of NATO for control of the blue-water ocean. As the Cold War progressed, however, it became clear that the Soviets could not win a toe-to-toe fight in the deep water, and the information sold to the Soviets by the Walker spy ring in 1980s made it clear that the ballistic missile submarines, in particular, were very unlikely to be able to carry out their nuclear attack missions.

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