I've toured it twice, a while back. Obviously it's very similar to the South Dakota class, and you would look hard to distinguish it from the Iowa class really. I didn't get why we had two classes at the same time so similar, I think it related to the naval treaty, but don't remember offhand.
It did. In accordance with the Treaty System based on the Washington (1922), London (1930), and Second London (1936) Naval Treaties there was a prolonged global pause in new Battleship and Battlecruiser construction.
Here are the final pre-pause Battleships/Battlecruisers for the US, Britain, and Japan:
United States:
The last pre-treaty Battleships of the USN were the Colorado Class ships. Four were planned and all four were launched before the treaty but one had to be scrapped to comply. The USN also had to convert two Lexington Class Battlecruisers then under construction into what became the Lexington Class Carriers Lexington and Saratoga. The Colorados had eight 16" guns, weighed ~32k tons, and had a top speed of 21kn. The Colorados were built 1917-1923.
Britain:
The last pre-treaty Battlecruiser of the RN was the Hood. Hood was originally to be one of four Admiral Class Battlecruisers but the other three were canceled due to lessons learned at Jutland and their replacements were never constructed due to the treaties. Hood had eight 15" guns, weighed ~45k tons, and had a top speed of 32kn. Hood was built 1916-1920.
The "Nelrods", Nelson and Rodney of the Nelson Class were the last pre-treaty Battleships of the RN. They had nine 16" guns (in an unusual all-forward layout), weighed 33k tons, and had a top speed of 23kn. The Nelrods were built 1922-1927.
Japan:
The last pre-treaty Battlecruisers of the IJN were the four ships of the Kongo Class. They had eight 14" guns, weighed ~27k tons, and had a top speed of 27.5kn. They were built 1911-1915.
The last pre-treaty Battleships of the IJN were the two ships of the Nagato Class. They had eight 16.1" guns, weighed ~33k tons, and had a top speed of 26.5kn. They were built 1911-1915.
Due to the treaties, no new Battleships or Battlecruisers were completed until the late 1930's in the run up to WWII. Hood was the largest warship in the world for 20 years.
After the pause the US built ten modern Battleships:
- 2 North Carolinas that more-or-less complied with the treaties (post-escalator clause)
- 4 South Dakotas that more-or-less complied with the treaties (post-escalator clause)
- 4 Iowas that were not limited by the treaties. Two more Iowas were nearly completed but never finished due to being surplus to late-war and postwar needs.
Britain built six:
- 5 KGV's that more-or-less complied with the treaties. One (PoW) was lost.
- 1 Vanguard completed after the war.
Japan built two:
- 2 Yamatos that were not limited by treaties. Both were lost and a third was completed as an aircraft carrier and also lost. The two completed as Battleships were the largest Battleships ever built and the aircraft carrier was the largest aircraft carrier ever built until the US built supercarriers much later.