Here's What You Need To Remember: It is at sea that the United States and China are most openly in competition. Today, U.S. warships regularly operate off of Chinese littoral water, but not vice versa.

Two superpowers eye each other uneasily across the Pacific—one well established after decades of Cold War conflict, the other a rising power eager to reclaim regional hegemony. Fortunately, despite profoundly different political systems, China and the United States are not as intrinsically hostile to each other as were the West and the Soviet Union—in fact, they have a high degree of economic interdependence.

Still, history shows that there is often a risk of war when a rising power challenges the ascendancy of an existing one. Beijing and Washington have profound—though fortunately not comprehensive—disagreements on matters of global governance. They also have reasons to mistrust each other. Fortunately, there are historical examples of rival superpowers coexisting mostly peacefully for long periods of time. For example, see the century in between the defeat of Napoleon and World War I, during which there was no European-wide war.

Still, the balance of power between nations will likely play a role alongside diplomacy—a fleet that is never used in war may still prevent one, for example, by deterring possible opponents.

China today has the largest military on the planet, with two million active personnel in the People’s Liberation Army (PLA). However, China only spends slightly over one-third as much as the United States, accounting for thirteen percent of annual global military spending in 2017, compared to thirty-five percent by the United States according to SIPRI.

Yet, the Chinese government is aware that the large size of its forces in part reflects an antiquated mid-twentieth century force structure emphasizing massive, low-quality ground armies. Starting in 2015, Chinese President Xi Jinping—who seems set to remain in power indefinitely—announced a major reform initiative to radically downsize PLA ground forces to improve their quality.

PLA ground and air forces still exhibit a wide range of quality, fielding both early Cold War systems and cutting-edge variants. For example, the PLA musters 8,000 tanks—but 3,000 are 1950s-era Type 59 and Type 63 tanks. At the same time, the PLA also fields 500 Type 99 tanks which are in a similar ballpark to the very capable U.S. M1 Abrams. The PLA Air Force also has a similar issue. For instance, of its 1,700 aircraft, roughly a third are dated J-7 fighters, while another fourth include modern fourth-generation J-10s and J-11s comparable to U.S. F-15s and F-16s and even a few fifth-generation stealth fighters.

By contrast, the U.S. military operates over two-thousand fourth-generation combat jets, increasingly being supplemented by fifth-generation stealth designs. These newer U.S. planes theoretically enjoy a massive edge in long-range aerial combat and in penetrating enemy airspace.

America's massive military spending reflects its technology-oriented approach to warfare, a paradigm which seeks to send a drone or guided missile in place of a man (or woman) whenever possible—especially as every friendly casualty may result in a political firestorm. Therefore, the Pentagon prefers to develop comprehensive intelligence and communication capabilities to direct a few weapons systems with a high degree of precision. This in contrast to fielding a larger, and cheaper, number of platforms which was typical in the past such as World War II. This paradigm favors ‘networked warfare', in which various weapons systems exchange sensor data. A ship, for example, may detect an attacking jet and pass the targeting data to a nearby fighter which can then use the telemetry to launch a missile without exposing itself by turning on its radar—or vice versa.

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China is also an enthusiastic adopter of this doctrine and has arguably made greater strides in developing armed drones and advancing networking capabilities than Russia or various European countries. On the one hand, Chinese industry still lags notably behind in the development of technologies such as jet engines and suffers quality control issues. However, on the other, it is relatively strong in the realm of electronics and is happy to copy both Western and Russian technologies. Furthermore, Chinese hackers have also proven reasonably adept at hacking into foreign computer systems and perpetrating industrial espionage, but Beijing has at least so far refrained from election-manipulation tactics practiced by its neighbor Russia.

Posture for Intervention Abroad and Defense At Home

Operationally, the PLA and U.S. military have very different needs. The U.S. is geographically isolated from its foes and instead depends on a massive network of overseas bases on six continents to engage or contain adversaries. This requires globe-spanning logistical capabilities including hundreds of transport planes, aerial refueling tankers to keep jet fighters and transports aloft, and amphibious transports and carriers to convey Marine units. Just as importantly, strong diplomatic alliances are necessary to maintain those overseas bases and keep them supplied with fuel, personnel and munitions. For example, U.S. operations in Asia are heavily dependent on alliances with South Korea, Japan, Singapore, the Philippines and more recently, India. Several of these Asian countries, as well as western and central Europe, also rely upon U.S. military forces to meet their security needs.

China is only beginning to acquire such logistics and is situated in a very crowded neighborhood surrounded by potential military competitors such as India, Russia and Japan. (Personally, this author does not believe contemporary Japan will become an aggressive military power anytime soon, but the Chinese don't see it that way due to their bitter memories of Japanese invasion.) Additionally, Beijing has only a few military alliances with Pakistan, North Korea, and a few southeast Asian nations. But, China is slowly developing multi-national institutions such as the Shanghai Cooperation Organization and its aspirational Silk Road project in hopes of fostering stronger ties.

However, China still retains tense relations with India, a country with a comparably huge population but only one-quarter of the gross domestic product, from which China seized Himalayan territory in a brief 1962 war. Moreover, Beijing has built up its forces and road network on its border with India, and also constructed a series of bases in nearby countries to ‘envelop' India.

China is also expanding its capacities for longer-range expeditionary operations befitting its status a superpower—particularly in Africa, where Chinese companies maintain a dominant and ever-growing presence. Beijing's non-interference and no-questions-asked approach to human rights and corruption issues have won it many friendly governments on the African continent.

For example, Chinese troops have deployed as peacekeepers in Mali, where they have seen some action, and recently opened a naval base in Djibouti—just seven miles across from a long-established American base there. The PLA and Peoples’ Liberation Army Navy (PLAN) have also concentrated on training a Special Forces and Marine branch suitable for more expeditionary operations.

Despite all of this, the United States military still has vastly more recent combat experience, particularly in joint operations coordinating multiple services. The PLA’s last major armed conflict was a not very successful punitive invasion of Vietnam in 1979. Today, the PLA is only beginning to implement a more joint-operations oriented doctrine while struggling to overcome the traditional parochialism of the military hierarchy, which occupies a prestigious place in its society.

Nuclear Doctrine

The United States maintains more than twenty times the number of nuclear warheads that China does (1,350 compared to 45 deployed and 4,000 compared to 270 when including stockpiles, according to the Arms Control Association). This reflects Washington's more aggressive nuclear posture, which holds that the U.S. has the right to launch a nuclear first strike in a conflict, even if it has only been attacked with conventional weapons. (Moscow has a similar stance, claiming it may use tactical nuclear weapons to ‘de-escalate' a conventional war.) China, by contrast, has a defensive nuclear doctrine claiming it will only employ nukes if attacked with them first.

While some might scoff at the distinction—after all, doctrine does not prevent a country from launching a first strike if it wants to—the reality is that offensive and defensive nuclear warfare involve different force structures. The United States has a massive arsenal in a nuclear ‘triad'. This is made up of ballistic missile submarines (which are basically so hard to hunt there is no way to stop them all); nuclear bombers (useful for signaling to an opponent the possibility of a nuclear attack, or for hitting mobile targets); and ground-based missile silos (the least flexible of the three, but these allow more targets to be hit and force an enemy to devote resources to attack them). Such an arsenal is capable of launching a broader assault designed to disable an opponent's military capability to retaliate and therefore more easily includes the option of a first strike.

In contrast, China holds a no-first-use doctrine because it maintains only nuclear ballistic missiles and a few ballistic missile submarines—though it may one day re-introduce a nuclear bomber component. China's smaller arsenal is also inadequate to deliver a knock-out first strike but is instead a deterrence-oriented ‘counter-value' force threatening nuclear annihilation of an adversary's largest cities were China to come under attack. Beijing has become nervous, in recent years, by the expansion of U.S. ballistic missile defense capabilities, which may eventually prompt a move to enlarge the arsenal.