The Iowa class Battleships (Iowa, Missouri, New Jersey, and Wisconsin) were not the largest class of battleship designed and ordered built by the US Navy. The Montana class approved by Congress and ordered built in 1939 was significantly larger, was much more heavily armored, and had significantly more throw weight from its main gun battery. Five named ships (BB-67 through BB-71) were authorized, the Montana, the Maine, the Ohio, the Louisiana, and the New Hampshire. Concurrently Congress also authorized the widening of the Panama Canal to accommodate the Montana’s. The construction of the Montana and her sister ships were delayed by the attack on Pearl Harbor and were ultimately cancelled after the sinking of the aircraft carriers Wasp, Hornet, Lexington, and the Yorktown in the Pacific war in favor of the much needed new Essex class aircraft carriers. The Montana’s would have been more than a match for the Yamato class battleships the Japanese were building as well as the German battleships the Bismarck and the Tirpitz.
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