You see, I don't think it would invalidate any laws... I suppose it would be subject to whatever judge is making the call, but I would imagine that any judge that's rational and logical would take into effect the concept behind the law, not just it's specific wording as it currently applies.

I hope that anyone looking at a law, written when that specific body of water was named "the Gulf of Mexico" and determine that, since it was called that at the time of the law being passed, that the law applies to the body of water that is, or was, known as "the Gulf of Mexico" at the time it was written, and the law continues to apply to that physical place, regardless of any changes in name.

But that might be a bit too logical, and I might be expecting a lot from the US Justice system.... Or any Justice system for that matter.