What is the only country to utilize paddle wheel propelled aircraft carriers?

The correct answer to this question is the United States. It is important for all aircraft operators to be trained properly. During the era of Pearl Harbor, the carriers the navy had couldn't be spared for training because an attack could happen at any time.

This is when the paddle wheel aircrafts came about, because it allowed aircraft operations to be trained without impacting the carriers that were already able to be used. USS Sable was one of the training ships. It was used on the Great Lakes, but sold in 1948 for scrapping. Another was USS Wolverine, which was also used on the Great Lakes.