The difference between freedom of navigation operations (FONOPs) and warships transiting under ‘innocent passage’ sounds arcane and legalistic. But this wonkish distinction is now central to understanding the nature of the US Navy’s activities in the South China Sea last week and going forward — with a critical bearing on how they are perceived in China and beyond.
USNI News, Defense News and Graham Webster all recently noted that the USS Lassen was undertaking innocent passage when it sailed past Subi Reef on 27 October. This surprising revelation has not been officially confirmed but is understood to have been widely corroborated by sources in the US Navy, Department of Defence and Capitol Hill.
It matters because the regime of innocent passage under the UN Convention on the Law of the Sea is specific to a country’s 12-nautical mile (nm) territorial sea. This allows warships to enter without notice but under constrained conditions, including that passage should be continuous and expeditious, with no use of on-board weapons, aircraft or ‘any act aimed at interfering with any systems of communication or any other facilities or installations of the coastal State’.
It was widely assumed that Subi Reef, as a low tide elevation now extensively built upon by China, was chosen deliberately as the location for the US Navy’s FONOP in order to demonstrate on clear legal grounds that the US does not recognise Beijing’s (or rival claimants’) jurisdiction over the surrounding waters. It is integral to the demonstration value of FONOPs against excessive claims that warships carry out ‘the normal range of activities which they would on the high seas, including manoeuvring, the use of active and passive sensors and even the operation of shipborne helicopters’. FONOPs and innocent passage are quite different things.