The Montana-class battleships hold a distinctive place in naval history, a combination of fantasy, dreams, and the rapid speed with which military technology can change. Built during a time when battleships represented the epitome of naval might, these ships were conceived as the biggest and most powerful that the U.S. Navy could produce. But after all the planning and expenditure put into them, none of them ever set sail. Their tale provides an interesting insight into how naval tactics were altered and how difficult choices can change the way the military is developed.
Before World War II broke out, battleships were the crowning jewel of any great fleet. Countries competed to construct larger guns and more armor, each attempting to one-up the other. The Montana-class was the U.S. response to that challenge, capitalizing on the speed and firepower of the Iowa-class battleships.
Meanwhile, other nations were envisioning their own “super-battleships,” although most of these ideas never made it beyond the drafting stage. Authorized by the 1940 Two-Ocean Navy Act, the Montanas were designed as a class of five, envisioned to take battleship design to its ultimate extremes.
In terms of size, the Montana-class would have been enormous. Loaded to their maximum capacity, the ships would have weighed more than 70,000 tons, outweighing the Iowas and coming close to the size of Japan’s Yamato-class. They were 921 feet long and 121 feet wide at the beam, and so large that the Panama Canal had to be enlarged to allow them through.
The guns of the ships were also impressive. They had twelve 16-inch guns, distributed in four triple turrets, three more guns than the Iowas and about 25 percent more firepower. The secondary armament had twenty 5-inch dual-purpose guns, more powerful than those on previous battleships, while a heavy concentration of smaller guns was intended to drive off planes, with provision for augmentation as air threat expanded.
Protection and armor were also top of mind in the design. The armor belt around the middle was a whopping 16.1 inches thick and sloped to deflect shells more effectively. Turret faces had protection of up to 18 inches, and important areas such as ammunition magazines and engine bays were provided with additional layers of armor. The hulls were formed carefully to withstand torpedoes and mines, and the Montanas were the first American battleships designed to survive direct hits from huge naval guns.
In exchange for all this power and protection, the Montanas were less quick than their Iowa-class forebears. They were driven by eight boilers generating 172,000 horsepower and could do 28 knots—quick by most measures, but not quick enough to outrun faster foes. This was indicative of a change in philosophy: these ships were built to survive and bring tremendous firepower to bear in so-called slugging matches, rather than depend on speed or agility.
World War II, nonetheless, revolutionized the face of naval warfare overnight. Aircraft carriers started playing a dominant role, demonstrating how battleships could be hit miles away by aircraft. The Pearl Harbor attack of 1941 bitterly established that even the best-protected battleships were susceptible to air attacks.
By 1943, despite the Montana-class ships being approved and funded, the Navy reluctantly cancelled them. The focus was shifted to constructing more aircraft carriers and finishing more Iowa-class battleships—a strategic move which kept the U.S. at naval dominance in the Pacific. If completed, the Montanas could already be surpassed by the ascendancy of air power, their huge guns made less effective because of the evolving dynamics of warfare.
Years have created myths about these enormous vessels. Some have painted them as enlarged Iowas with an additional turret, or ships constructed to compare with the Yamato. The Montana-class actually was a new design, with stronger secondaries and increased armor, planned without definite knowledge of opposition designs. Another falsehood is that they went beyond Panama Canal constraints; in fact, though they were larger than the current locks, expansion plans were being made, and other clearance problems, like the Brooklyn Bridge by the New York Navy Ya, held the real impediment.
The Montana-class battleships are the peak and also the decline of the battleship era. Their cancellation wasn’t an engineering or vision failure, but rather an acknowledgment that naval warfare had shifted in a new direction. By prioritizing aircraft carriers and more multi-purpose ships, the U.S. Navy set itself up for supremacy in the years to come. The Montanas are still an intriguing “what if,” a reminder that, however powerful a weapon might appear, developments in strategy and technology can rapidly reposition its role in history.
