You are in another country as soon as you drop anchor or tie up. I would assume that it would aply to another state as well. If you boat into NY but never drop anchor your still under CT law. There are no freeking lines out there and it goes back to before the days of GPS and high tech navigation but that is the law. Now you can go from state to state just put your gun in one lock box and your ammo in another and you can transport over state lines as I have been told by police and many other gun carriers in MA. I also have a licens to carry concealed in MA and I enjoy going ot he range. When I have to carry say 100 grand worth of equipment through a not so good part of town you better believe I prepair for the worst and pray to God for the best.