On balance, critics' arguments that ratification of UNCLOS would impede PSI do not hold up under scrutiny

Which view is correct? It is shaky, if not totally ill-founded, for UNCLOS opponents to suggest that the implementation of the PSI will be affected negatively by U.S. accession to UNCLOS. No persuasive arguments exist to the contrary.

Gaffney provided some reasons explaining why U.S. accession to UNCLOS would hinder its ability to pursue PSI’s goals.¹⁵⁴Gaffney, Frank. "Statement of Frank Gaffney, Jr.: Oversight Hearing to examine the "United Nations Convention on the Law of the Sea". (March 24, 2004) ." Testimony before the U.S. Senate Committee on Environment & Public Works, March 24, 2004. [ More (3 quotes) ] However, he failed to mention the possibility that the United States could stop and board a vessel on the high seas which was flying the flag of a country like Panama, Liberia, the Marshall Islands, Croatia, Cyprus, or Belize, all of which have signed bilateral shipboarding agreements with the United States.¹⁵⁵ In addition, it is also likely that the United States would obtain the consent from a flag state to interdict a vessel on the high seas, if reasonable evidence is provided or it is supported by reliable intelligence that the vessel concerned is indeed carrying or transporting WMD- related cargo. Moreover, while UN Security Council Resolution 1540 does not explicitly authorize the interdiction of a foreign-flagged vessel on the high seas which is suspected of carrying or transporting WMD-related cargo, it can still be argued that action taken under the PSI would not be inconsistent with the call for cooperation to confront the threat posed by WMD proliferation set out in the Resolution. Furthermore, Gaffney argued that the ability of the United States to undertake PSI interdiction action would be affected by Article 88 of UNCLOS, which declares that the high seas are reserved for peaceful purposes, and by Article 301, which obligates states parties to refrain from “the threat or use of force against the territorial integrity or political independence of any State.”¹⁵⁶ However, these two provisions can also be cited by the United States as grounds for interdicting foreign- flagged vessels on the high seas if it is reasonably suspected or sufficiently proven that these vessels are carrying or transporting WMD-related cargoes that are to be used by the “states of proliferation concern” for nonpeaceful purposes or have the potential to affect international peace and security. The foreign-flagged vessels’ right to enjoy the freedom of navigation on the high seas in accordance with Article 87 of UNCLOS and the exclusive jurisdiction of the flag state over these vessels on the high seas under Article 92 are to be subject to certain limitations.

Gaffney may be correct where a vessel flying the flag of North Korea and having declared in the ship’s manifest that it is transporting Scud missiles to Yemen could not be intercepted without a breach of the UNCLOS.¹⁵⁷ However, interdiction on the high seas is not the only option for stopping the transport of WMD-related goods or technologies from a state of proliferation concern. As the 1993 Yinhe incident demonstrates, the U.S. Navy could follow a suspect vessel and request cooperation from the port state to conduct an investigation once the vessel enters its port. Under UN Security Council Resolution 1540, a port state is obligated to take cooperative action to prevent illicit trafficking in WMD and WMD-related materials.¹⁵⁸

Gaffney also argued that, if the United States remains nonparty to UNCLOS, it would not be subject to the limitations under the Convention.¹⁵⁹ However, as pointed out by Moore, it is wrong to assume that the United States is free from any constraints in relation to its ocean actions if it does not accede to UNCLOS since the United States is bound by the 1958 Geneva Conventions on the law of the sea which are more restrictive than UNCLOS on issues relating to the PSI.¹⁶⁰

In sum, the better view is that of the Bush administration regarding the potential impact of U.S. accession to UNCLOS on the implementation of the PSI. The views held by some of the opponents to UNCLOS are arbitrary and shaky, and lack persuasive reasoning. It is incorrect to argue that the PSI is barred by UNCLOS. After all there are 18 states fully participating in PSI and more than 70 countries that have expressed their support for the Initiative, and most of these countries are party to UNCLOS. Moreover, while UNCLOS is considered the most important legal instrument in dealing with the rights and obligations of states in the oceans, there are other international treaties, regimes, and frameworks that can be relied on if interdiction actions against suspect vessels that carry or transport “WMD, their delivery systems and related materials” to and from “states and non-states of proliferation concern” are necessary.