The U.S. and China’s Nine-Dash Line: Ending the Ambiguity | Brookings (2024)

  • 8 min read

For the first time, the United States government has come out publicly with an explicit statement that the so-called “nine-dash line,” which the People’s Republic of China (PRC) and Taiwan assert delineates their claims in the South China Sea, is contrary to international law. Assistant Secretary of State for East Asian and Pacific Affairs Danny Russel, in testimony before the House Committee on Foreign Affairs on February 5, said, “Under international law, maritime claims in the South China Sea must be derived from land features. Any use of the ‘nine-dash line’ by China to claim maritime rights not based on claimed land features would be inconsistent with international law. The international community would welcome China to clarify or adjust its nine-dash line claim to bring it in accordance with the international law of the sea.”

The South China Sea encompasses several hundred small islands, reefs, and atolls, almost all uninhabited and uninhabitable, within a 1.4 million square mile area. The PRC inherited from the former Kuomintang government of China the nine-dash line, which draws a line around all of these islands, asserts sovereignty over all of them, and makes ambiguous claims about rights to waters within the line. Under the U.N. Convention on the Law of the Sea (UNCLOS), negotiated in the 1970s and 1980s, countries can claim exclusive rights to the fish and mineral resources within Exclusive Economic Zones, which can extend 200 nautical miles from a continental shore line or around islands that can support habitation. There is no provision in the convention granting rights to waters, such as in the South China Sea, without regard to land-based sovereign rights. So it has long been implicit in the U.S. interpretation of UNCLOS that claims to the mineral and fish resources of the South China Sea, unless they are linked to specific inhabitable islands, are invalid. Assistant Secretary Russel’s statement has made that position explicit.

U.S. attention to the South China Sea has increased visibly under the Obama administration. The first manifestation of that attention was a highly publicized statement by Secretary of State Clinton at an international gathering in Hanoi in 2010, in which she laid out principles governing U.S. policy in the South China Sea: respect for freedom of navigation, peaceful resolution of disputes, freedom of commerce, negotiation of a Code of Conduct for dispute resolution and, most relevant here, the view that claims to water could only be based on legitimate land-based claims. Clinton’s statement took a hitherto obscure, below the radar issue and made the South China Sea the subject of accelerated regional diplomacy, numerous analyses by commentators and national security specialists and in some cases sharpened rhetoric by the various claimants. It was welcomed by all of the Southeast Asian claimants (i.e., Vietnam, Philippines, Malaysia, Brunei), though resented by China.

Secretary Clinton made the statement in response to growing concern among China’s neighbors that China was advancing its claims through political and military means and in the absence of any diplomatic process to reduce tensions. In 1994-1995, there had been a similar period of heightened tensions when China built installations on Mischief Reef in the Spratly Islands, claimed by the Philippines. A deterioration in Chinese relations with Southeast Asian countries led the Chinese leadership, spearheaded by then State Councilor Qian Qichen, to negotiate a regional Declaration of Conduct and a pledge not to take actions that would change the status quo. Sporadic seizure of fishing vessels by one party or another continued, and countries, principally Vietnam, granted exploration rights to oil companies in disputed areas, but none of these episodes triggered war alarms.

In the last several years, however, there has been a growing concern in the region, and in the U.S., that China had turned its back on diplomacy and was using military and legal means to advance its claims to all of the South China Sea. Statements to U.S. diplomats characterizing the South China Sea as an issue of prime importance to China involving sovereignty and on which it would not accept interference raised the ante. In 2012, China expelled Filipino fishermen from traditional fishing grounds around Scarborough Shoal, less than 125 miles from the main Philippine islands, and has used its coast guard to maintain control. In 2012, it established an administrative and military district covering portions of the claimed Paracel Islands. In establishing an Air Defense Identification Zone over portions of the East China Sea in late 2013, Chinese spokesmen indicated an intention at some point to establish a similar zone in the South China Sea, which inevitably would cover at least some areas claimed by others.

The South China Sea is a complicated issue for the United States. We have no territorial claims there. We do not take sides on the respective sovereign claims of the parties, nor should we. It is highly unlikely that any country can establish effective means of projecting power from South China Sea islands that would threaten U.S. ships, military or otherwise, in the region. While there are believed to be considerable unexploited reserves of oil and gas within the South China Sea waters, they are not commercially viable for production on a large scale and are not expected to be for some time.

But the U.S. does have important interests in the South China Sea. They are:

  • To ensure freedom of navigation, not as a favor from any country but as an international right in an area through which 50 percent of the world’s oil tankers pass, that is a major thoroughfare of international commerce, and where U.S. military vessels deploy and operate consistent with international law.
  • To prevent use of force or coercion to resolve claims either to territory or to maritime rights.
  • To advocate for respect for international norms and law for resolving all such issues.
  • To ensure that all countries, including the U.S., have the right to exploit the mineral and fish resources outside of legitimate Exclusive Economic Zones.
  • To prevent a U.S. ally, the Philippines, from being bullied or subject to use of force.
  • To ensure that the rights of all countries, not merely large ones, are respected.

There are tensions between differing elements of U.S. interests. The U.S. does not wish to see China gain control over the area through coercion. But at the same time the U.S. does not have an interest in making the South China Sea a venue of confrontation or conflict between the U.S. and China. Frontal challenges to Chinese claims, if not founded on international norms and consistent with U.S. principles, run the risk of inciting heightened Chinese nationalism and paranoia over U.S. intentions and producing more aggressive Chinese behavior in the region that would victimize the other claimants without an effective U.S. response. On the other hand, a passive U.S. posture would undercut the interests outlined above and would persuade the other claimants that the U.S. was abandoning both them and our principles, thereby making a mockery of the Obama administration’s “rebalancing” toward Asia and badly damaging regional receptivity to U.S. presence and influence.

By explicitly rejecting the nine-dash line, Assistant Secretary Russel and the administration have drawn our own line in the right place. They have made clear that our objection is a principled one, based on international law, not a mere rejection of a claim simply because it is China’s. So long as our approach to the South China Sea remains firmly grounded on principle and international law, the U.S. can accomplish our objectives, strengthen the position of other claimants with respect to their rights and avoid the appearance of seeking confrontation with China over a sovereignty issue.

What else can and should the U.S. do? Several things:

  • The U.S. should ensure that its approach is not seen as unilateral. It is not, but sometimes other countries are publicly quiet but privately supportive. The U.S. government should make clear to the other claimants, and to other ASEAN countries like Singapore and Thailand, that we expect them to be public in their rejection of the nine-dash line under international law.
  • The U.S. should discuss with Taiwan whether it can clarify its position on the nine-dash line, to make clear that its claims are consistent with UNCLOS.
  • The U.S. should continue to make a high priority negotiation of a Code of Conduct between China and the ASEAN states, as we have done since Secretary Clinton announced that objective in Hanoi. Indeed, the decision by China and ASEAN to begin talks on a Code of Conduct was one of the beneficial outcomes of Secretary Clinton’s statement.
  • The U.S. should urge the Chinese not to establish any new Air Defense Identification Zone in the South China Sea. While a public position on this is necessary, private diplomacy is likely to be more effective in influencing Beijing.
  • The U.S. should discuss with all the claimants possible agreement on exploitation of mineral and fish resources without regard to sovereignty, including the use of joint ventures between companies.
  • The Senate should ratify the U.N. Convention on the Law of the Sea. That would give the U.S. legal and moral standing to participate more actively and effectively in decisions on the future of the South China Sea. All former U.S. Secretaries of State support such a decision. So does the U.S. Navy and former Chiefs of Naval Operations and Pacific Commanders. So does the overwhelming majority of concerned U.S. companies. We should put our money where our mouth is.

More On

  • Sub-Topics

    China Southeast Asia Taiwan


Foreign Policy


ChinaSoutheast AsiaTaiwan


John L. Thornton China Center

The TikTok debacle: Distinguishing between foreign influence and interference
The U.S. and China’s Nine-Dash Line: Ending the Ambiguity | Brookings (3)

Social Media The TikTok debacle: Distinguishing between foreign influence and interference

Diana Fu, Emile Dirks

June 24, 2024

Unleashing “new quality productive forces”: China’s strategy for technology-led growth
The U.S. and China’s Nine-Dash Line: Ending the Ambiguity | Brookings (4)

China Unleashing “new quality productive forces”: China’s strategy for technology-led growth

Arthur R. Kroeber

June 4, 2024

How China would tackle a second Trump term
The U.S. and China’s Nine-Dash Line: Ending the Ambiguity | Brookings (5)

Geopolitics How China would tackle a second Trump term

Yun Sun

May 31, 2024

The U.S. and China’s Nine-Dash Line: Ending the Ambiguity | Brookings (2024)


How does China justify the 9 dash line? ›

China has indisputable sovereignty over the islands in the South China Sea and the adjacent waters, and enjoys sovereign rights and jurisdiction over the relevant waters as well as the seabed and subsoil thereof (see attached map).

Why did Barbie include the nine-dash line? ›

It demonstrates a fierce resistance to any legitimacy that China's ongoing South China Sea nine-dash line claims may generate, even in Barbie's fictional world.

Which countries are affected by China's nine-dash line? ›

The nine-dash line area claimed by the Republic of China (1912–1949), later the People's Republic of China (PRC), which covers most of the South China Sea and overlaps with the exclusive economic zone claims of Brunei, Indonesia, Malaysia, the Philippines, Taiwan, and Vietnam.

What is the US stance on the South China Sea? ›

The United States makes no territorial claim in the SCS and takes no position on sovereignty over any of the geographic features in the SCS, but U.S. officials have urged that disputes be settled without coercion and on the basis of international law.

What said the US should have equal trade rights in China? ›

The Open Door policy was a statement of principles initiated by the United States in 1899 and 1900. It called for protection of equal privileges for all countries trading with China and for the support of Chinese territorial and administrative integrity.

Why does China want spratly? ›

Basis for the PRC's and the ROC's claims

Chinese fishermen have fished around the islands since 200 BC. China claims to have discovered the islands in the Han dynasty in 2 BC. The islands were claimed to have been marked on maps compiled during the time of Eastern Han dynasty and Eastern Wu (one of the Three Kingdoms).

Why was Barbie banned in China? ›

Vietnam has banned the new “Barbie” film because it features a map showing China's claim to the South China Sea.

What movies are banned because of the nine-dash line? ›

Vietnam Bans 'Barbie' Movie Because of 'Nine-Dash-Line' in Map of South China Sea.

What is the controversial map in the Barbie movie? ›

Story highlights. Led by Margot Robbie, Barbie will release on July 21. The film's trailer drew flak after it featured a world map that represented "nine-dash line" which reinforces China's territorial claims in the South China Sea.

Which country has no borderline with China? ›

Cambodia does not share a border with China. It is a Southeast Asian nation that shares its border with Thailand, Laos, Vietnam and the Gulf of Thailand.

Who owns the Spratly Islands? ›

Background. The Spratly Islands consist of more than 100 small islands or reefs surrounded by rich fishing grounds -- and potentially by gas and oil deposits. China, Taiwan, and Vietnam all claim the islands in their entirety, while portions are claimed by Malaysia and the Philippines.

What country is China trying to claim? ›

"Taiwan, China", "Taiwan, Province of China", and "Taipei, China" are controversial political terms that claim Taiwan and its associated territories as a province or territory of the People's Republic of China.

Why is China aggressive in the South China Sea? ›

Stealing Resources in the South China Sea

Beijing uses intimidation to undermine the sovereign rights of Southeast Asian coastal states in the South China Sea, bully them out of offshore resources, threaten them out of shipping lanes, assert unilateral dominion, and deprive fishermen of access to their livelihoods.

What country controls the South China Sea? ›

Both the People's Republic of China (PRC) and the Republic of China (ROC, commonly known as Taiwan) claim almost the entire body as their own, demarcating their claims within what is known as the "nine-dash line", which claims overlap with virtually every other country in the region.

What is the cabbage strategy? ›

Cabbage tactics is a militarily swarming and overwhelming tactic used by the People's Liberation Army Navy to seize control of islands. It is done by surrounding and wrapping the island in successive layers of Chinese naval ships, China Coast Guard ships, and fishing boats and cut off the island from outside support.

Why is the number 9 special in China? ›

The ancient Chinese considered numbers a mystical part of the universe. As an odd number, the number "9" belongs to the "yang" category, which represents strength and masculinity. In ancient China, the number "1" represented the starting point while the number nine represented infinity and extremity.

Why does China think it owns the South China Sea? ›

In 1947, China issued a map detailing its claims, and insists history backs up its claims - Beijing says its right to the area goes back centuries to when the Paracel and Spratly island chains were regarded as integral parts of the Chinese nation. These claims are mirrored by Taiwan.

What is China's fault line? ›

The Longmenshan Fault (Chinese: 龙门山断层) is a thrust fault which runs along the base of the Longmen Mountains in Sichuan province in southwestern China. The strike of the fault plane is approximately NE.

Top Articles
Latest Posts
Article information

Author: Jerrold Considine

Last Updated:

Views: 5501

Rating: 4.8 / 5 (58 voted)

Reviews: 89% of readers found this page helpful

Author information

Name: Jerrold Considine

Birthday: 1993-11-03

Address: Suite 447 3463 Marybelle Circles, New Marlin, AL 20765

Phone: +5816749283868

Job: Sales Executive

Hobby: Air sports, Sand art, Electronics, LARPing, Baseball, Book restoration, Puzzles

Introduction: My name is Jerrold Considine, I am a combative, cheerful, encouraging, happy, enthusiastic, funny, kind person who loves writing and wants to share my knowledge and understanding with you.