Becuase no existing tugboat was powerful enough to pull Musashi's stupidly huge body, a large tugboat was built specifically to serve Musashi: Sakufuu Maru

430 tons 1600 horsepower

Drunk again?

This is simply about the fact that there was a tugboat built specifically for Musashi, but not that this one tugboat was towing Musashi all the time or anything like that.