Tensions escalate in the South China Sea as China’s “Wall of Sand” continues to grow.

Over the past six years, unilateral and escalatory actions by claimants to territories in the South China Sea have exacerbated tensions in the region.

China has not been the precipitator of the tensions in these waters — whether it be in initiating resource exploration activities in disputed areas, introducing military vessels to enforce jurisdictional claims, or conducting land reclamation work in the adjoining waters. In each instance, other claimants were the first to roil the waters.

But China’s response to actions by other claimants has been heavy-handed, disproportionate to the provocation at hand and, at times, designed to destabilise an already-delicate situation. That said, none of the actions by claimants, China included, has violated international law — even if some of the actions have operated in grey areas where definitive rules are lacking (such as in respect of the status of maritime historic rights). The same cannot be said about recently-publicised actions by the US Navy in these contested waters.

On 20 May, a US Navy P-8 Poseidon surveillance aircraft directly flew over a Chinese administered artificial island constructed atop a Spratly’s feature (the Fiery Cross Reef) in the South China Sea. The American crew insisting that it was flying through international airspace. The overflight was provocative, dangerous and inconsistent with international law. Worse, the most senior US diplomat for the East and Southeast Asia region appears not to grasp this, insisting that the flight was ‘entirely appropriate’.

International law on artificial islands, installations and structures is very clear. The UN Convention on the Law of the Sea reads: ‘In the exclusive economic zone, the coastal state shall have the exclusive right to construct artificial islands, installations and structures; the coastal state shall have exclusive jurisdiction over such islands; [it] may, where necessary, establish reasonable safety zones around such islands … [so long as these zones do] not exceed 500 metres around them, measured from each point of their outer edge; [all vessels] must respect these safety zones’.

China is legally entitled to reclaim and construct artificial islands and installations in the sea areas adjacent to the land features that it administers within the Spratlys chain. There is no rule in international law that bars a coastal state from undertaking this kind of reclamation at sea.

And, so long as the feature resides within the 200-nautical-mile exclusive economic zone (or median line thereof) of an ‘island’ administered by China in the Spratlys, Beijing is entitled to reclaim and build atop that land feature — even if it is submerged at high-tide. Three of Beijing’s seven administered features in the Spratlys protrude above sea level at high-tide and could comport to the technical definition of an ‘island’. If Itu Aba/Taiping Island — an ‘island’ that is administered by Taiwan — is considered to be Chinese territory as per the ‘One China’ policy, then every China-administered feature in the Spratlys chain is encompassed within this exclusive economic zone area up to the median line.

China also has the right to exercise exclusive jurisdiction over the waters and airspace above the artificial island, out to perimeter of 500 metres from its outer edges. Establishing such a safety zone has nothing to do with unilateral enforcement of a military exclusion zone or an air defence identification zone (ADIZ) as some have claimed.

It follows that the US Navy by directly flying over the artificial island has violated Beijing’s rights. Admittedly, the US is not a party to the Law of the Sea Treaty and hence is not bound by its strictures. By the same token, the US’ customary navigation and overflight freedoms do not override the prescriptive treaty-based rights that accrue to Beijing in the airspace and adjoining waters of its artificial islands, installations and structures.

The flights are not just legally untenable and dangerously escalatory; they also have implications beyond the immediate legal infringement. Specifically, they are also a standing invitation to the Chinese to send surveillance flights through the airspace directly above the disputed Senkaku/Diaoyu islands. In November 2013, Beijing declared an ADIZ in the East China Sea, which controversially included the airspace over these disputed islands. China has until now refrained from conducting non-commercial flights through this airspace. But it would be within its rights as a claimant to take such provocative and unwise action. It is extremely unwise for Washington to lay the groundwork for such behaviour through its own errant actions in the South China Sea. To rein in its Spratlys overflights would be the sensible course.

The driver of America’s actions in the Spratlys is a growing and pervasive mind-set within the Beltway that insists that the US must ‘do something … anything’ to demonstrate active resolve in the face of regional anxiety over China’s use of military and paramilitary force to allegedly change the status quo.

If that is indeed a sensible strategic objective, US (and other claimants’) naval vessels and aircraft could operationally assert their navigational and overflight freedoms beyond the 500-metre safety zone of China’s artificial islands that are built atop low-tide elevations. Such features are not entitled to a territorial sea. Common sense would dictate that as a precaution the overflights should be kept some distance away from the 500-metre zone.

But no party in the South China Sea should engage in non-commercial passage through the airspace above an artificial island, installation or structures that they do not administer or are obliged to protect. For the United States to do so would be to violate international law; for other claimants to do so would be to engage in dangerously provocative actions.

High seas navigational and overflight freedoms in the waters adjoining the disputed land features in the South China Sea have not been violated, despite a rhetorical tendency to inflate the threat to these freedoms. The exercise of these freedoms, especially by non-claimants, should not interfere with the sovereign rights and jurisdiction of those who are claimant parties in these waters.

Sourabh Gupta is a Senior Research Associate at Samuels International Associates, Inc., Washington, D.C. This article was originally published in the East Asia Forum on 26 May, 2015. It is republished with permission.