First island chain

The first island chain refers to the first chain of major archipelagos out from the East Asian continental mainland coast. Principally composed of the Kuril Islands, Japanese Archipelago, Ryukyu Islands, Taiwan, the northern Philippines, and Borneo; from the Kamchatka Peninsula to the Malay Peninsula. Some definitions of the first island chain anchor the northern end on the Russian Far East coast north of Sahkalin Island, with Sahkalin Island being the first link in the chain. However, others consider the Aleutians as the farthest north-eastern first link in the chain. The first island chain forms one of three island chain doctrines within the Island Chain Strategy.

The first island chain has its purpose in Chinese military doctrine. The People's Republic of China views the first island chain as the area it must secure and disable from American bases, aircraft and aircraft-carrier groups, if in defending itself it must tactically unleash a pre-emptive attack against an enemy. The aim of the doctrine is to seal off the Yellow Sea, South China Sea and East China Sea inside an arc running from the Aleutians in the north to Borneo in the south. According to reports by American think tanks CSBA and RAND, by 2020, China will be well on its way to having the means to achieve its first island chain policy.

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