So, five oil tankers are steaming to Venezuela from Iran, with the U.S. determined to stop them, and Iran telling they darn well better not, or else. So, what really are the US’ options, and what might be the consequences?
So, let’s start with the United Nations sanctions on North Korea. In 2017, Security Council Resolution 2375 permitted countries to stop and inspect vessels on the high seas with the consent of the country providing flagging services to the vessel. The flagging country can alternatively direct the vessel to a port for inspection – or it can refuse (in which case the third party country is supposed to report the details to the UN for possible designation of the vessel). That would seem to imply, therefore, that the normal ability to stop vessels is much more limited… which it is.
Enter the Law of the Sea… specifically the UN Law of the Sea Convention (UNLOSC) enacted in 1982. On the high seas (i.e. outside the territorial waters of a country), there are very limited instances in which vessels can legally engage each other. These include suspected involvement in narcotics trade, slavery and piracy – there are a few more (like illegal broadcasting). In addition, a country can track down another vessel while in “hot pursuit” if the pursuit started in the pursuing country’s territorial waters and has continued uninterrupted. If none of those conditions apply, the Law of the Sea says that vessels (aircraft and ships) are entitled to navigate freely.
So, it would seem there is no legal way for the U.S. to intervene, other than through threats… or so you would think.
Turns out the United States never ratified the 1982 UNLOSC (it did the earlier 1958 one), although the NOAA (National Oceanographic and Atmospheric Administration) website says that the U.S. “recognizes that the 1982 Convention reflects customary international law and complies with its provisions.” However, the 1958 Convention has no provisions regarding pursuit and really only focuses on the right of passage through territorial waters.
So, it could stop those tankers if it wanted…
Not without consequences, I suspect. Might other non-signatories of the 1982 Convention change their posture as to how they interact with other vessels on the high seas? Might signatories back out of UNLOSC to level the playing field with the U.S.? Or, perhaps, vessels like these tankers that might be in jeopardy of seizure start having military escorts?
I hope we don’t find out the answers to those hypotheticals any time soon…