Customary international law is entirely inadequate for protecting underseas cables

Critics of UNCLOS raise the argument that since many of the rights spelled out in UNCLOS can be considered customary international law to which the US adheres, there is not need to formally ratify the convention.

From first hand experience, I can say this academic argument fails in the real world. Customary international law requires a court decision to determine state practice, before it can be said to be binding law. Last year I involved in a non-cable major marine pollution case pending in a US court where the issue was the rights of a European coastal nation to refuse entry to a leaking supertanker after the crew had been rescued. I think the issue is well addressed in UNCLOS, but both sides presented expert witnesses and detailed memorandums arguing for different interpretations of what the applicable state practice and customary international law is. Ultimately, we won't know the answer until the Judge decides the issue. The point is that telecom companies can not make business investments on such an illusive basis as customary international law. They need reliable and discernable international law which UNCLOS expressly provides.