Center for Maritime Strategy – On November 30th, 2023 the Spanish Navy (“Armada Española”) received the S-81 Isaac Peral, the first of four diesel-electric attack submarines of the S-80 Plus class, built by Spanish shipbuilder Navantia. The S-80 program is expected to revive the Navy’s diminished submarine fleet by 2028 and significantly enhance Spain’s maritime surveillance and area denial capabilities. The S-80-class submarines come at a time when the Spanish Navy is under-resourced to meet the strategic requirements and threats imposed by its current maritime environment.