However ill-advised some of MacArthur’s actions in Korea and elsewhere; and however excessively-Taiwan-centric, exaggerated, or otherwise unrealistic the above maritime domino theory might be to implement fully in practice; his island chain philosophy indeed encapsulates some important strategic thinking of the era. Such thinking unquestionably influenced Chinese strategists as they sought to make sense of their nation’s geostrategic position, the security challenges it faced, and what it might do to address them.

 

China’s Appropriation of the Concept

In formulating their own views on the island chains, Chinese military theorists frequently look back on American strategic ideas from the mid-twentieth century. Many Chinese sources refer to early Cold War-era statements articulating the need for a U.S. defensive perimeter in the Western Pacific, such as that proposed by MacArthur and others, including Dean Acheson and John Foster Dulles. Tracing the origin of the concept, one Chinese military scholar states: “The term ‘island chain’ originated from the proposal made by Western countries led by the United States after World War II by taking advantage of the strategic geographic locations of some special island groups in the Northwest Pacific Ocean waters to suppress and block socialist countries at the time, such as the Soviet Union and China.”

Contemporary Chinese strategic thinking related to the island chains emphasizes the early Cold War-era U.S. strategy of constructing a defensive perimeter meant to contain the Soviet Union and its Chinese ally. As we chronicle in a recent China Quarterly article, Chinese military writings frequently refer to the island chains as barriers imposed by the United States that limit China’s ability to evolve into a genuine maritime power with freedom of maneuver throughout the Western Pacific. A 2007 article in the Chinese navy’s official magazine, for instance, declares that the island chains have the power to “contain China and the Chinese navy.” Two Chinese naval strategists similarly argue that the “partially sealed-off nature of China’s maritime region has clearly brought negative effects on China’s maritime security.” Moreover, harkening back to American activities in the 1950s, contemporary Chinese writings often portray U.S. force deployments in areas such as Guam, the Philippines, and Okinawa as the result of “Cold War thinking” designed to contain China.

A similar strand of Chinese military thinking conceives of the island chains as “springboards” from which the U.S. military can conduct operations close to Chinese sovereignty claims. For instance, retired PLAN Rear Admiral Zhang Zhaozhong has identified Guam as a strategic location from which the United States can “immediately send out aircraft or dispatch submarines, in order to put power into the war zone,” referring to the Taiwan Strait.

In contrast to these views of the island chains as the locus of threats posed by the U.S. military, some Chinese military theorists see the island chains more as benchmarks for Chinese military operations. This mode of thinking is most prominent among naval strategists. Admiral Liu Huaqing argued that, for the foreseeable future, most naval operations would be confined to the First Island Chain, which he defined as including Japan, South Korea, Taiwan, the Philippine Islands and the Greater Sunda Islands. But, as a long-term goal, Liu argued that China must be prepared to eventually operate out to the Second Island Chain, including the Mariana Islands, Guam and Palau. Chinese media frequently details progress towards this goal, describing in almost heroic terms the voyages of successive Chinese naval flotillas through the strategic passageways of the First Island Chain, and into more distant waters. For some, then, the island chains have become markers in China’s attempts to develop a “blue water” navy capable of performing both wartime and peacetime missions.

 

The Island Chains’ Enduring Relevance

Beyond the exigencies of specific planning scenarios, why do strategists from so many nations periodically fix their gaze—explicitly or implicitly—on the island chains? They do so because these long strings of land features have intrinsic geostrategic value. There is a basic geo-operational reason for this. Military platforms and their crews generally require support from appropriately-positioned terrestrial bases for their high-performance, sustained, cost-effective operation. As any glance at a globe reveals, the Pacific Ocean is vast, containing 714 million cubic kilometers of water, 50.1 percent of global seawater. It covers 165.25 million square kilometers (63.8 million square miles)—significantly more than the Earth’s total landmass of 150 million square kilometers (58 million square miles); and equivalent 46 percent of Earth’s water surface and one-third its total surface area. The rapidity and intensity of modern military operations place an additional premium on overcoming this “Tyranny of Distance” expeditiously. Basing military assets in-region, or at least enabling and supporting their deployment there, offers an unrivaled solution.

Yet the Pacific’s unparalleled expanse contains relatively few specks of land, widely dispersed. In the entire Pacific Ocean—including the home islands of Japan, the Philippines, and New Zealand; as well as Taiwan, Hainan, Papua New Guinea, and Hawaii—there are only 20 islands larger than 10,000 square kilometers (3,861 square miles). In the South Pacific (excluding Papua New Guinea), home to the majority of the ocean’s islands, the total landmass is only 551,913 square kilometers (213,095 square miles).

These factors put an inherent premium on the military value of any given Pacific feature, particularly the very few of sufficient size, resources, and human capital to host an advanced military facility. Hence, the late nineteenth century preoccupation with “coaling stations” to power the increasingly-long-range operations of the U.S. and other navies; the Imperial Japanese efforts to gain control of Pacific islands, both to enjoy their use and deny it to the United States; the protracted island hopping campaigns of the Pacific War; and the extraordinarily-rapid, -dramatic American transformation of re-captured islands such as Guam into major militarily facilities, at a cost possibly prohibitive in conditions short of world war.

To be sure, the island chains’ precise strategic value, and hence strategists’ specific emphases on them, has varied significantly as a function of changes in military technology and application—including what weapons are based on them, how far those weapons can reach, and whether it is possible to defend and supply them. This value changed significantly during the interwar period. It shifted profoundly during the Pacific War (which, among other things, highlighted the need for air defenses to protect ships and land installations and the importance of submarines in severing supply lines). Today, it is shifting greatly once more, with the advent of much longer-range strike systems (aircraft, anti-ship cruise missiles/ASCMs, land-attack cruise missiles/LACMs, conventional ballistic missiles); and defensive systems (long-range surface-to-air missiles/SAMs). These developments are dramatically increasing the range of shore-based systems versus those based on ships—a dynamic that Chinese planners have exploited deftly and systematically. This might also apply to the value of individual islands like Taiwan, which is not placed to expand China’s power projection capability significantly, but (by virtue of geography) could in theory offer a potent “springboard” for a foreign military to attack mainland China. Such theory might have accorded with empirical reality in 1980, but this is certainly much less the case today given the PLA’s ability to crater runways; attack command and control with precision strike weapons; and use long-range SAMs to attack aircraft as soon as they are airborne. In short, given today’s Chinese weapons, Taiwan is too close to mainland China to have maximum “strategic value.”

Island chains are the subject of focus as much for their exceptional vulnerability as for their exceptional capabilities, however. Their very concentration offers an enemy a conveniently-circumscribed target set. In today’s era of long-range precision strike (LRPS), the problem has become nothing short of acute. Not for nothing has China developed and deployed the world’s largest, most diverse sub-strategic conventional ballistic missile force. Beijing now has the ability to strike more islands, in more ways, more effectively; Washington and its allies must think how best to respond.

At the geopolitical level, as documented earlier, the island chains, like the region they shape geophysically, have long been regarded as important fulcrums of world affairs. Today, as the U.S. Pacific Command emphasizes,

“The 36 nations comprising the Asia-Pacific region are home to more than 50% of the world’s population…several of the world’s largest militaries, and five nations allied with the U.S. through mutual defense treaties. Two of the three largest economies are located in the Asia-Pacific. . . . The [region] includes the most populous nation in the world, the largest democracy, and the largest Muslim-majority nation. . . . The region is a vital driver of the global economy and includes the world’s busiest international sea lanes and nine of the ten largest ports. The Asia-Pacific is also a heavily militarized region, with seven of the world’s ten largest standing militaries and five of the world’s declared nuclear nations. Given these conditions, the strategic complexity facing the region is unique.”

The island chains have long been considered particularly relevant to opposing an authoritarian continental state’s attempt to dominate Eurasia, a central imperative of U.S. strategy since its ascendance to the world stage since the late nineteenth century. During the Pacific War, Tokyo—with its sweeping seizure of Chinese territory—arguably constituted precisely such a challenge. Throughout much of the Cold War, Washington mounted geopolitically-similar opposition to both Chinese and Soviet efforts to dominate Eurasia. Recently, with China’s rise and Russia’s military resurgence, at least some Western strategists perceive analogous dynamics.