At extreme gun calibres, adding armour can cease to be an automatic answer because thick structure may simply give an incoming shell material in which to detonate. Once weapons exceed roughly 18 inches, this argument places more weight on internal subdivision, watertightness, and many small compartments that confine damage. The N3 still represents the armoured-battleship extreme of its generation, built to absorb repeated punishment while returning 18-inch fire. The watch point separates protection philosophy from a simple thickness contest and shows why designers have to balance resistance, damage localisation, and weapon effects.
Notable Point · 44:07-45:08
When more armour can make a shell more destructive
Against shells larger than 18 inches, survival may depend less on ever-thicker armour and more on subdivision that confines flooding and blast damage.