Ships, and the oceans they sail, are governed by a confounding tangle of laws. No one state exercises sovereignty over the high seas, so ships are subject to a complex—and easily ignored—combination of international maritime law, treaties, and the national codes of coastal states and flag-granting countries; at times they seem to defy terrestrial rules altogether. Over the past few decades journalists and academics have chronicled the “lawless ocean,” documenting widespread human rights abuses in the shipping and fishing industries and what might be termed “the outlaw sea.”* In Empty Vessel, Ian Kumekawa, a historian at MIT and Harvard, finds that the seas are in fact replete with laws—but that many of them are designed to get around other laws, to exploit or create loopholes, or to obtain regulatory and tax advantages, all with the goal of maximizing profits for shipping companies. This parallel offshore universe of laws and contracts was slowly built up by lawyers, corporations, and territories that function as tax havens, enabling them to reap profit without paying their due—and becoming central …