Summary and Key Points: The Montana-class battleship was designed to be too wide to fit through the Panama Canal. At 121 feet across the beam and 921 feet long, displacing over 71,000 tons fully loaded, it would not have passed through locks that were 110 feet wide — and the US Navy signed off on that anyway, because a ship that could outfight anything afloat was worth more than a ship that could take a shortcut between oceans. Twelve 16-inch guns in four triple turrets, three more than an Iowa carries. A belt of armor 16.1 inches thick. Five ships were ordered. Not one keel was ever laid.
The Montana-Class Battleships: Better Than the US Navy Iowa-Class?
The Montana-class was envisioned as the pinnacle of U.S. battleship design, surpassing the Iowa-class in size, armor, and firepower.
They were projected to displace about 63,000 tons standard and over 71,000 tons at full load, making them significantly larger than their predecessors.
At 921 feet long and with a beam of 121 feet, they were too wide to pass through the Panama Canal’s original locks, a clear indication of their massive scale.
Their draft was approximately 36 feet, and they were designed for a top speed of 28 knots, slower than the Iowa-class’s 33 knots but still respectable for their size.
Propulsion would have come from steam turbines generating 172,000 shaft horsepower across four screws.
In terms of armaments, the Montana-class was unparalleled. Each ship would have mounted twelve 16-inch/50 caliber guns in four triple turrets, giving them a heavier broadside than any U.S. battleship before or since.
Their secondary battery consisted of twenty 5-inch/54 caliber dual-purpose guns, supplemented by dozens of anti-aircraft weapons, including up to forty 40 mm Bofors and fifty-six 20 mm Oerlikons.
Armor protection was equally impressive, with a belt thickness of 16.1 inches, turret faces up to 22.5 inches, and deck armor reaching 7.35 inches. These ships were designed without treaty restrictions, unlike earlier classes, and would have rivaled Japan’s Yamato-class in size and protection, making them the most formidable battleships ever planned by the U.S. Navy.
What if the U.S. Navy Actually Built the Montanas?
What would have happened if the Montana-class had been built?
Had these ships entered service by 1944 or 1945, they would have been unmatched in gun power and armor.
In a hypothetical surface engagement, they could have destroyed Yamato and Musashi with superior radar-directed fire control and heavier broadsides.
Their twelve 16-inch guns would have delivered devastating salvos at long range, while their thick armor could withstand enemy shells.
However, such engagements were rare by late World War II.
Iowa-Class Battleship USS New Jersey Creative Commons Photo
The last major battleship duel occurred at Surigao Strait in October 1944, where older U.S. battleships annihilated Japanese forces.
By then, carriers ruled the seas. Montana-class ships would likely have served as shore bombardment platforms during island-hopping campaigns, similar to the Iowa-class. Their massive firepower could have shortened battles like Iwo Jima and Okinawa.
If completed, the Montanas might have remained in service through Korea and even Vietnam, providing naval gunfire support.
Their imposing presence could have served as a Cold War deterrent, much like the Iowa-class battleships, which were reactivated in the 1980s.
However, the rise of guided missiles, jet aircraft, and nuclear submarines would have relegated them to niche roles.
Maintaining such giants would have been costly, and they likely would have been retired by the 1960s or converted into missile platforms.
Strategically, building the Montana-class might have delayed carrier production, potentially altering the timeline of U.S. dominance in the Pacific.
If resources had shifted to battleships, fewer carriers might have been available for critical battles like Leyte Gulf. This could have prolonged the war or increased U.S. casualties. In short, their construction might have been a strategic misstep, despite their impressive specifications.
Why America Transitioned to Aircraft Carriers
The historical context of the Montana-class is rooted in the collapse of naval arms limitation treaties.
The Washington and London Naval Treaties of the 1920s and 1930s capped battleship displacement at 35,000 tons and gun caliber at 16 inches, forcing compromises in earlier designs such as the North Carolina and South Dakota classes.
USS North Carolina battleship.
By the late 1930s, these treaties had effectively collapsed, and intelligence reports suggested Japan was building massive battleships, revealed as Yamato and Musashi.
The U.S. Navy responded by planning a class that could outgun and outlast any adversary.
However, the attack on Pearl Harbor and subsequent battles, especially the Coral Sea in May 1942 and Midway in June 1942, proved the decisive role of aircraft carriers.
Carrier-based airpower could strike hundreds of miles away, rendering traditional battleship duels increasingly obsolete.
By 1943, the Navy prioritized Essex-class carriers, landing craft, and destroyer escorts over new battleships.
The Montana-class was canceled before any keel was laid.
Montana-Class Battleship vs. Iowa-Class. Image Credit: Creative Commons.
Iowa-class battleship artist painting. Image Credit: Creative Commons.
Several factors doomed the Montana-class.
The most significant was the shift in naval strategy toward carrier warfare, which dominated the Pacific theater. Battleships became secondary assets, mainly for shore bombardment and escort duties.
Resource allocation also played a role; steel, manpower, and shipyard capacity were urgently needed for carriers and amphibious vessels.
The Montana-class ships were slower than the Iowa-class, making them less suitable for operating with fast carrier task forces.
Finally, the cost and complexity of building five super battleships during wartime were impractical compared to producing multiple carriers and escorts.
About the Author: Isaac Seitz
Isaac Seitz, a Defense Columnist, graduated from Patrick Henry College’s Strategic Intelligence and National Security program. He has also studied Russian at Middlebury Language Schools and has worked as an intelligence Analyst in the private sector.
