Barbiano exposes the risk of designing for one opponent

Barbiano served during the Spanish Civil War, fought at Calabria, and later spent time as a training ship because Italian leadership recognized the class as under-armored. The design assumptions reflected a specific French opponent and a central Mediterranean operating environment. British destroyers were structurally heavier because they were expected to operate across the Atlantic, Indian Ocean, Mediterranean, and Pacific. Entering war against Britain therefore changed both the tactical opponent and the sea conditions the cruiser had to survive.