Your hailing port is where your vessel claims origin. You can choose your hailing port to be anywhere you would like, provided it is a place in the United States. Specifically, so long as it is in the U.S. Department of Commerce’s Federal Information Processing Standards Publication 55DC, you can select a designated location or place as your hailing port. Coastal, landlocked, you can choose anywhere you would like.
Your hailing port does not have to be the vessel’s physical location nor where it resides the most. In fact, it does not have to be anywhere the vessel is registered, either.