The Montana-class battleships were the final grand design of an age in which naval power was measured by thick armor walls and the din of giant guns booming across the oceans. They were to be the ultimate realization of American battleship design, constructed to surpass even the mighty Iowa class in sheer protection and firepower. But for all the zeal that pushed them, none of these ships ever left the drafting table, superseded by a new kind of war that was to redefine the seas for all time.
Warship architecture had been contained in straitjackets by interwar treaties for years, with restrictions placed on size, gun caliber, and armor. The Montanas were intended to free themselves at last from such constraints.
At 121 feet in width, they would have been too large to pass through the original Panama Canal locks, and thus plans were made for entirely new, wider locks to accommodate them.
Design on the class preceded formal American entry into the Second World War, with Congress authorizing the first two ships in 1939. Design conformed to the Navy’s established philosophy—maximum armor and maximum firepower—but this was at the sacrifice of the speed that made the Iowa class so renowned.
If constructed, the Montanas would have been better armed than any previous or subsequent American battleship. Their armor was designed to withstand the colossal 2,700-pound Mark 8 “superheavy” shell, more lethal than anything previous designs were thought to be able to withstand.
Their main belt was a record 16.1 inches thick at an obliquity for even more effectiveness. Above that, there was to be a second belt for protection from shells skipping underwater and impacting below the waterline.
Above, stacked deck armor was to be positioned for both protection from plunging naval gunfire and the armor-piercing air bombs dropped from the air.
The guns they carried were to be accompanied by virtually impenetrable gun turrets. With barbettes up to 21.3 inches and barrels up to 22.5 inches, no other American design came anywhere near providing the same degree of turret protection.
Even underwater attacks were addressed: the Montana class had an elaborate torpedo defense system with alternating liquid- and air-filled layers designed to scatter the shock of explosions. This was one of the more advanced configurations ever put on paper, intended to permit the ships to take a pounding and still be able to fight.
Ultimately, however, the Montana class never came to be. The war hysterics turned from battleships to fast carriers and other naval needs. The Montanas, all promise and possibility, were part of a conception of war that passed.
Left was the concept of them—giant, unstoppable vessels of steel and gunpower—that became legend without ever showing up in the ocean.