What foreign navies could learn from CSS Hunley

What did other navies think of CSS Hunley's partly successful attack?

It showed an underwater attack could work, but Hunley's loss obscured the lesson and revealed how hazardous her weapon and operating arrangement were.

The panel treats Hunley's attack as both a technical warning and a difficult event for contemporary observers to interpret. Other navies could ask whether the idea might work against them and how to defend against it. Yet Hunley disappeared soon after the attack, limiting immediate understanding of what had happened. Her spar-torpedo arrangement and the crew's position also made the mission dangerously close to self-destructive, which is why the panel calls her a submersible rather than a mature submarine.