Former Defense Secretary Donald Rumsfeld has an excellent article up at the Wall Street Journals website on why the U.N. should not hold preeminence in law enforcement on the seas. The main crux of the matter is that with 90% of all trade being moved over the sea at some point forfeiture of a nation to police trade in hulls owned it's citizens amounts to a de facto acknowledgement of the supremacy of the international community. That de facto acknowledgement could easilly be argued as a case against a nation's ultimate sovereignty, while this has little legal ramification, circumstances that would cause the legal sovereignty of a modern nation are almost unthinkable after all, there is the issue of national prestige for Americans.
We are a nation that fought a war of rebellion to have the power of self determination, we aren't the French or Germans, the Swiss or the Belgians, who in the name of economic growth and multiculturalism bowed down and accepted the authority of the European Union, nor should we be so meek when it comes to our trade across water, we Americans are masters and commanders of our own fate and should refute the power of an organization so notably corrupt and venal as the United Nations when it comes to commerce over the waters. The Law of the Sea Treaty was foolishness thirty years ago, and time has not lent it a veneer of wisdom!