China is more aggressively pushing into international waters. (Photo by iStock.)

Chinese military aircraft and warships have been entering the airspace and waters around the Korean Peninsula and the seas between South Korea and Japan more frequently since late 2017.

According to the United Nations Convention on the Law of the Sea (UNCLOS) states have freedom of navigation. Thus, Chinese military aircraft and warships entering the waters between South Korea and Japan, where Chinese geography does not extend natural maritime territorial rights, is still within the bounds of international law. However, there are some things to consider here.

First, Chinese entries increased beginning in late 2017 to two areas of particular importance.

They increased their ventures into Korean air and waters. The number of Chinese military aircraft entries to the Korea Air Defense Identification Zone (KADIZ) has increased from 50 in 2016, to 80 in 2017, 140 times in 2018, and 150 times in 2019. In the case of warships, Chinese warships have been crossing the Exclusive Economic Zone (EEZ) provisional equidistant line and appeared near the Korean Peninsula. This has increased from 110 times each year in 2016 and 2017, to 230 in 2018, 290 in 2019, and 170 times as of Aug. 31, 2020. While China and South Korea have never reached a mutual agreement on the delimitation of their respective EEZs due to differing interpretations of what would constitute an “equitable solution,” the increase in the number of warships illustrates that the Chinese are engaging in more aggressive behavior than before regarding maritime boundaries.

China has also increased its ventures into territory between Korea and Japan. Long-range flights by Chinese military aircraft to the area around the island of Ulleungdo, located 120 kilometers east of the Korean Peninsula, between South Korea and Japan, have been taking place since late 2017. Until around 2015 or 2016, unauthorized entry of Chinese aircraft had been mainly limited to neighboring areas in the Yellow Sea, which separates China from the Korean Peninsula.

Second, this behavior follows a regular pattern. China entered the KADIZ over the sea between South Korea and Japan, without prior notification to Seoul, with great regularity at the end of each month. For example, military aircraft have made fairly regular entries at the end of the month: in 2018, they entered on Jan. 29, Feb. 27, April 28, July 27, Aug. 29, Oct. 29, Nov. 26 and Dec. 27. Such a regular pattern of behavior indicates that China views this area not as a transit space, but rather as zone of potential military operations.

Third, about 27 states in the world have an air defense identification zone, which is not defined in international law. However, while China demonstrates that it does not recognize KADIZ, as it usually refuses to give prior notification of its transit movements to Seoul, China still requires flight plan, radio, responder, and logo identification information from international aircraft entering the Chinese Air Defense Identification Zone (CADIZ). This gives the lie to the Chinese assertion that it does not recognize KADIZ and exposes its double standard.

What does all this mean?

First, the increased entries into South Korea’s claimed EEZ and KADIZ, and forays into the waters between South Korea and Japan, which are not connected to China geographically, represent some strategic changes within the Chinese security apparatus. They can be read as China’s countermeasure against the beginning of the deployment of the Terminal High Altitude Area Defense (THAAD) in South Korea in September 2017. However, though these ventures may have started as a response to THAAD initially, they can also be read as China’s ambition to go and secure what military strategists have described as its “first island chain,” encompassing all of the waters of the Yellow Sea, the waters between the Korean Peninsula and Japan, the East China Sea and the South China Sea, as bordered by the island chains at their northern, eastern, and southern extremities. According to Chinese Air Force expert Fu Qianshao, who was interviewed in The Global Times, the Chinese navy is conducting regular trainings in the waters between the Korean Peninsula and Japan. Another person interviewed by The Global Times, who asked not to be named, said that in the future —whether China is to build a strategic air force or a strategic navy — going through the first island chain will become the normal training of the Chinese navy and air force, further supporting this assessment.

Second, this signals a power vacuum in the region. Late 2017 saw an increase in Chinese forays into the waters between the Korean Peninsula and Japan. While this could have been an initial response to THAAD deployment, it nonetheless coincided with the adoption of the Indo-Pacific strategy by the U.S. in October 2017. The Indo-Pacific concept was first outlined in January 2007 by the Indian naval strategist Gurpreet Khurana in the academic journal Strategic Analyses, and the first world leader to publicly use the term, in 2007, was then-Japanese Prime Minister Shinzo Abe. The concept vision was finally adopted by the U.S. in 2017, under then-U.S. President Donald Trump.

Accordingly, the U.S. changed the name of its Pacific Command to the Indo-Pacific Command in 2018 to reflect this. Such emphasis on the region from the Pacific Ocean to the Indian Ocean gives even more weight to the Indian Ocean and America’s relationship with India. If the U.S. shifts enough of its military assets to focus on the Indian side of the Indo-Pacific region, then the Pacific side could become less important than it has been previously.

China appears to be expanding its operation zone to the edges of the first island chain. Once China secures this, its logical next step would be to penetrate deeper into the Pacific and challenge the U.S. more directly. If South Korea and Japan cannot deal with this threat effectively, the strategic balance of the region can be further shaken, which would only be favorable to China.


— Hayoun Jessie Ryou-Ellison, Ph.D., is nonresident senior fellow at “Indian Military Review.”

The 2020 Edition of the Journal of Peace and War Studies (JPWS)

2020 cover to the peace and war journal

The 2020 JPWS edition addresses a most challenging issue in the current global community—escalation of the U.S.-China rivalry.

In addition to this issue’s peer-reviewed scholarly articles, four Norwich University students — John Hickey, Shayla Moya, Kathryn Preul, and Faith Privett — explain America’s foreign policy blunders in Afghanistan utilizing the Just War theory. They also suggest political, economic, and military approaches that could bring stability in conflict-stricken Eastern Ukraine.

Read online or download the 2020 JPWS Journal

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