Admiral Andrew Cunningham steered HMS Warspite straight into the lion’s den, gunning to corner the Italian Royal Navy in a fierce clash right off their own coastline. It was a bold gamble that promised either a sweeping victory or a catastrophic defeat.

Although battleships were replaced by aircraft carriers by the end of World War II, they remain a testament to a bygone era of warfare—and a symbol of their nations’ might. For nearly half a century, the battleship was the singular symbol of a nation ...