International straits and transit passage

This article on Japantoday.com.

"Japan set narrow territorial waters along straits for U.S. nukes"

This was actually something that I learnt quite some years ago (maybe 8 years?) when I was studying the law of the sea (known as the United Nations Convention on the Law of the Sea, or UNCLOS).

Some straits, because of geographical location and history, have been traditionally used by ships (merchant or naval) for getting from one place to another. These straits are recognised as international straits under UNCLOS, and all ships have the right of transit passage through international straits. This right allows naval ships to transit through international straits in their normal mode of operation (compared to innocent passage, which limits the activities that can be carried out while en route), which means that they can continue to fly aircraft, operate sonars, operate fire control and weapon systems, submarines can remain submerged while on transit, etc.

If Japan were to exercise her territorial rights and claim up to 12nm of territorial waters from her coast, some of these international straits will be totally Japanese territorial waters (because they are less than 24nm wide). In such as case, for warships transitting through these straits, they can actually go as close to the Japanese coast as they want to fly aircraft, operate weapons, submarines can remain submerged while on transit, etc. as long as it is their normal mode of operation.

By not claiming the full 12nm, but only up to 3nm from the coast, the middle portion of these international straits are no longer Japanese territorial waters. Ships are free to transit through this portion of the straits claiming right of passage. There is thus no reason for them to enter Japanese territorial waters. This means that all ships entering within 3nm of the Japanese coast will now become restricted by the right of innocent passage (which means that submarines will have to surface for transit, aircraft will need permission to fly, ships are not allowed to operate their weapon systems, etc.)

So while it may sound foolish to claim 3nm when you can have 12nm, sometimes more doesn't mean better.