Cecil mentions the Rush-Bagot Treaty demilitarizing the Great Lakes.
As an aside, while there haven’t been permanent naval forces on the Great Lakes, there has been plenty of naval construction on the Great Lakes.
Here’s a long list of U.S. naval vessels and submarines built in Wisconsin, for example.
The lack of the St. Lawrence Seaway didn’t prevent ships from getting to the ocean-- for example, Gato-class submarines built by the Mantiwoc Shipbuilding Company sailed down Lake Michigan to Chicago, traveled down the Chicago River, the Sanitary & Ship Canal, the Illinois River, the Mississippi then finally the Gulf and the oceans.
It’s been possible for lake vessels to get to the ocean since the opening of the Erie Canal, but initially only small ones. The passage of larger vessels was made possible by the opening of the Sanitary and Ship Canal in the early twentieth century. According to Wikipedia, the depth of the S&S Canal is 24 feet. The draft of the real battleship Illinois was 23.5 feet, so if all the stars were aligned I suppose a lake/ocean transit might have been possible at some point prior to the Seaway opening in 1959. However, the depth of the canal today is said to be 21 feet, and that of the Illinois Waterway downstream much less, so I’m skeptical that such a passage would have been a practical possibility.
The extra fun part about Wikipedia is that now the article includes Uncle Cecil’s comment about the Seaway as an additional reason why the ship was a replica, rather than remove the unsupported and spurious assertion about Rush-Bagot.
There’s an article about the wooden “battleship” USS Recruit, built in NYC’s Union Square in May 1917, in the June 2022 issue of Naval History magazine; see p. 8.
There were locks on the St. Lawrence to allow ships to pass through well before the Seaway was built. I’ve just written a book about the submarine S-49, which passed up the St. Lawrence to be exhibited in Chicago in 1933, and passed back down in 1938. There had been two other subs that went from the Atlantic to the Great Lakes before 1933. One of them, a German sub, the UC-97 is still there, at the bottom of Lake Michigan.