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The South and East China Sea disputes: recent developments

Published Wednesday, November 7, 2018

For some time the Library has been tracking the territorial disputes in the South China Sea and East China Sea, publishing several background briefings about them. This note provides a short overview of the main developments in these disputes since 2016.

Over the last two years, an increasingly self-confident China has maintained an assertive posture in both disputes, while seeking to avoid outright conflict with its global and regional rivals  – above all, the US, Japan and southeast Asian states. At the same time, broader relations between China and the US have become increasingly strained. 

While for many experts the South China Sea dispute is the more volatile of the two, some worry that the East China Sea dispute could ultimately pose a bigger threat to international peace and security because it is more likely to draw the US into a direct conflict with China through its close alliance with Japan under their 1951 Security Treaty.

In both disputes, the prospects for resolving their ‘root causes’ look close to zero. If this assessment is correct, the best that can realistically be hoped for is the effective management of tensions in order to prevent uneasy stalemates deteriorating into outright conflict. 

South China Sea...

Many analysts consider that the balance of forces has shifted significantly towards China in the South China Sea since 2016, in large part as a result of its extensive island-building and base-construction activities in the Paracel and Spratly Islands, which have been accompanied by a build up of military equipment on them.

In April 2018, the Commander of the US Pacific Command argued that “China is now capable of controlling the South China Sea in all scenarios short of war with the United States.”

Over the last year, the US has been more active in its efforts to combat China’s alleged militarisation of the region. It is also determined to assert the right to ‘freedom of navigation’ of commercial and military shipping/aircraft in the South China Sea. China says that it too supports the principle – but it has adopted a narrower definition. There have been a number of 'close encounters' between US and Chinese vessels and aircraft - the most recent was just a few days ago.

In May 2018, the US withdrew an invitation to China to take part in a ‘Rim of the Pacific’ military exercise.

US allies like Japan and Australia have also been intensifying their presence in the region. All are offering support to southeast Asian states interested in strengthening their military capabilities, including Vietnam and Indonesia. The UK role also seems to be on the increase. In August and September, Royal Navy ships conducted freedom of navigation operations in the South China Sea. There is speculation that the Navy’s new aircraft carrier may visit the region soon after it enters service in 2020. 

China has successfully deployed economic incentives to moderate or deflect regional opposition to its territorial claims over the past two years. The Philippines, which won a landmark case at the UN challenging China’s territorial claim in July 2016, has for now apparently abandoned the legal route, opting instead, at least for now, to ‘hug’ China close.

There has been some progress on confidence-building measures between China and southeast Asian states – in August 2017, they agreed a framework for negotiations on a code of conduct for the South China Sea – but it is unclear whether such initiatives are more about buying time for China to create more ‘facts on the ground’ than about improving stability in the region. China remains opposed to a legally binding code of conduct. In October, southeast Asian states also agreed non-binding guidelines on how to manage aircraft encounters in the South China Sea. Both China and the US have agreed in principle to abide by these guidelines. Guidelines for naval encounters were agreed in 2014.

...East China Sea...

Over the last two years or so, following a period of high tension from 2012-15, the main rival claimants in the East China Sea, China and Japan (the other is Taiwan), have managed to somewhat calm the situation. The two countries have continued to test each other out and build up their military capabilities, and there have been numerous flashpoints, but overall the number of ‘skirmishes’ has been down.

The US and Japan have continued to conduct regular joint military exercises in recent years – to which China always strongly objects. But both China and Japan have said that they want to move towards more normal relations. In May 2018, after a decade of negotiations, they agreed to establish a ‘Maritime and Aerial Communication Mechanism’. It became operational in June.

The International Crisis Group welcomed the May 2018 announcement:

The new hotline it includes will connect Chinese and Japanese military chiefs via their embassies, enabling faster and smoother communication between decision-makers in case of an incident at sea or in the air. The pact also commits defence officials to hold regular meetings and implements a mechanism for their naval ships to communicate directly, in line with the Code for Unexpected Encounters at Sea (CUES), to which both are party […] The Maritime and Aerial Communication Mechanism is helpful both as a practical tool and a signal of political intent to prevent clashes. Japan and China should follow it by committing to manage disputes and encounters with professionalism, dialogue and diplomacy, and to have their planes and vessels refrain from risky or intimidating behaviour.

... there is also a wider dispute between the US and China over EEZs

In addition to the two territorial disputes, China is also asserting a general right under international law to regulate the activities of foreign military forces operating within the whole of its 200-nautical-mile Exclusive Economic Zone (EEZ). This position is taken by around 20 other States. The US and other States argue that international law gives coastal states the right to do this only within the 12-nautical-mile territorial waters that make up part of an EEZ.

According to a recent report by the US Congressional Research Service, this dispute “appears to be at the heart of incidents between Chinese and US ships and aircraft in international waters and airspace” – for example, in May 2016, when Chinese fighters flew within 50 feet of a US naval electronic surveillance aircraft in the South China Sea – and is as significant for the US as the territorial disputes. The UK supports the US position. 

Further reading

International Crisis Group, ‘Crisis Watch’ summaries of monthly events in the South China Sea and East China Sea

The Senkaku/Diaoyu Islands: tension between Japan and China in the East China Sea, House of Commons Library briefing paper, April 2013

 The US-Japan Security Treaty and the East China Sea, House of Commons Library briefing paper, May 2014

 The South China Sea dispute: July 2016 update, House of Commons Library briefing paper, July 2016 

Ryan Hass, “The risk of a US-China confrontation in the East China Sea”, Brookings Institution, 20 December 2017

China’s Actions in South and East China Seas: Implications for U.S. Interests—Background and Issues for Congress, Congressional Research Service, 1 August 2018

Veerle Nouwens, “Collision course in the South China Sea?”, RUSI, 3 October 2018

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