Additonal Insured
I find it hard to believe that an insurance company would balk at naming anyone who has a legitimate insurable interest in your vessel's liability as an additional insured. If the state and the Donald are involved (as underlying lessor/owner, lessee or management agent I'd expect), the insurance co shouldn't have a problem. If these parties are so involved, it may be their lease or management agreements with your harbor that require the harbor to require that of its tenants. Who insures the other boats in the harbor?