A comprehensive review of the territorial integrity of the international law of the sea

Insularity—the idea of islands as unique landforms—has been around for ages in international law. Even with its long history at global conferences, the concept keeps showing up in articles of the Convention on the Law of the Sea. Sounds simple enough: an island is just land surrounded by water. But it’s not that easy. Countries can’t agree on exactly what counts as an island, or how this definition should work in practice. Things get even trickier when it comes to drawing maritime boundaries. Insularity plays a big part in deciding how far a country’s rights stretch into the sea, and in sorting out where one country’s waters end and another’s begin. Naturally, this leads to plenty of legal debates. In this article, I dig into what “island” really means in international law. I use library research and a descriptive-analytical lens to pin down the legal status of islands, and to look at how much island status actually matters when countries set their maritime boundaries. I bring in what states have argued, what international courts and arbitrators have decided, and what legal experts have to say. When you look closely, the standard definition of islands mostly lines up with customary law, and it’s usually straightforward when just figuring out a single country’s maritime area. But when it comes to splitting up sea zones between countries, things get messy. The outcome often depends on what the countries involved want, and on the judgment of legal authorities. Because of that, island status often has only a limited effect—or sometimes hardly any effect at all—on how those lines get drawn.