How China has modernized their navy to dominate the South China Sea and beyond

Those who observe China's specific modernization goals, as well as their expressed intents in their actions, have determined that the PLAN's mission most likely focuses on the following goals:

1. To possibly curb Taiwan's continued attempts at independence militarily.

2.  Asserting or defending China's territorial claims in the South China Sea and East China Sea and generally exercising more control over the South China Sea, where trillions of dollars of trade pass through every year.

3.  Enforcing China's assertion that it has a legal right to regulate foreign military activities in its 200-mile maritime exclusive economic zone, despite the protestations of their neighbors in the region.

4. Defending China's commercial sea lines of communication with military and trading partners.

5. Usurping the US as the dominant power regional power in the Western Pacific, and promoting China as a major world power.

Source: Congressional Research Service

China's DF-21D "Carrier Killer" ballistic missile is the cause of much concern for US naval planners. The missile has a tremendous range of about 810 nautical miles, far beyond the range of a US aircraft carriers highest endurance planes, effectively denying them the luxury of lurking off China's coast in the Western Pacific while in striking range.

The DF-21D uses a range of sensors to adjust its course during firing. This means that it can hit a moving target at sea in sub optimal conditions, and presents difficulties to any missile trying to intercept it. The DF-21D can deliver a high explosive, radio frequency, or even a cluster warhead, which all but guarantee a kill even against a formidable target such as a US aircraft carrier.

Source: Congressional Research Service 

The PLAN's submarine fleet continues to undergo a modernization push that focuses on "counter-intervention" tactics against a modern adversary. The force has acquired 12 of Russia's Kilo-class diesel-electric submarines and launched no fewer than four new classes of indigenously made submarines, all of which are vastly more capable than the Cold-War era vessels they're replacing.

The PLAN has launched two diesel-electric (Song and Yuan class), and two nuclear classes (Jin and Shang class). But the Shang class was stopped after only two hulls were produced, which led the DoD to speculate that the PLAN may be exploring an updated version of this class.

As the DoD states:

Over the next decade, China may construct a new Type 095 nuclear powered, guided-missile attack submarine (SSBN), which not only would improve the PLA Navy’s anti-surface warfare capability, but might also provide it with a more clandestine, land-attack option.

Additionally, the Jin class can be armed with 12 JL-2 nuclear-armed submarine-launched ballistic missiles, which given the submarine's range, could potentially hit any of the 50 states in the US from locations in the Pacific. 

Source: Congressional Research Service

The PLAN's Russian-bought submarines remain some of the most capable in the fleet. Eight of the 12 Kilo classes (presumably the newer ones) carry the Russian-made SS-N-27 Sizzler cruise missiles, with a range of over 180 miles.

Source: Congressional Research Service

Here a Chinese YJ-18 anti-ship cruise missile performs an "S" shaped maneuver as after launch to help avoid interception.

The PLAN possesses a large, varied inventory of cruise missiles. Some of their most capable missiles are Russian made, like the  SS-N-22 Sunburn and the SS-N-27 Sizzler, but their indigenously made missiles are also rated highly.

China's YJ-18 cruise missile goes into a supersonic sprint phase when approaching a target, making it harder to stop. Other rangy platforms like the YJ-62, fired from surface ships, and the YJ-12, that can be fired from bombers, complicate the US's naval plans with their versatility. 

Source: Congressional Research Service

The PLAN's sole carrier, the Liaoning, has been referred to as a "starter" carrier, as its limited range and capabilities have made it primarily useful as a training craft. Having an aircraft carrier allows the PLAN to test carrier-launched aircraft and carrier strike group procedures in a realistic way. 

The Liaoning has a displacement of about 50,000 tons, and can support about 30 aircraft. US Nimitz class carriers double both of those figures, and also provide catapults to launch planes with heavier weapons and fuel loads, increasing their range. 

As the Liaoning is conventionally powered, and not nuclear powered like the US carriers, it's ability for long range power projection is greatly diminished. 

Source: Congressional Research Service

China is thought to be making rapid progress towards building additional aircraft carriers. Little is known of the China's future carriers, but they will most likely also feature the ski-jump platform of the Liaoning. 

Source: Congressional Research Service

With the help of the Liaoning, the PLAN has succeeded in fielding the J-15 "Flying Shark" carrier-based aircraft.

The J-15 is modeled after Russia's Su-33 "Flanker," just as much of China's military hardware borrows from Russian designs. On land, the J-15 has a range of about 745 miles, but launching the plane from a ski-jump style carrier platform means that it cannot carry as much fuel, and therefore has a reduced range. Only eight production J-15s are known to be flying at this time.

It has been previously reported that the PLAN seeks to create a short takeoff, vertical landing plane for carrier-based use in the future. However, they still lack carrier-based reconnaissance plane like the US's E-2 Hawkeye.

Source: Congressional Research Service

The PLAN's Air Force has been steadily developing new aircraft for "missions including offshore air defense, maritime strike, maritime patrol, antisubmarine warfare, and, in the not too distant future, carrier-based operations."

The PLAN has been replacing their aging Chengdu J-7 variants and Shenyang J-8B/Ds with 24 Su-30MK2s, which were purchased from Russia in 2002.

Additionally, the PLAN has a licensed copy of Russia's Tu-16 Badger bomber, the H-6 Badger, of which they likely have 30. The bombers are escorted by JH-7 Flounder fighter/bombers.

The PLAN, like most modern navies, is also pouring money into drones.

"Some estimates indicate China plans to produce upwards of 41,800 land- and sea-based unmanned systems, worth about $10.5 billion, between 2014 and 2023," according to the DoD.

Source: Congressional Research Service

Much like the submarine program, the PLAN's fleet of surface combatants has grown rapidly since 1990, with the purchase of four Sovremenny-class destroyers from Russia and the launch of 10 new classes of indigenously built destroyers and frigates, as well as a new class of corvettes.

US naval planners consider several of the newer frigate classes to be nearly as capable as Western models, and note that shipboard air defense have notably improved in the newer classes.

China's coast guard, which it wields as a sort of paramilitary force for enforcing their maritime claims, has also benefited from a large number of new cutters.

The newer ships have sophisticated radar and missile capabilities across the board, and future vessels are expected to truly rival the systems used by the US.

Source: Congressional Research Service

According to the Dod:

China has built four large YUZHAO class amphibious transport docks, which provide a considerably greater and more flexible capability than the older landing ships, signaling China’s development of an expeditionary warfare and OTH (over the horizon/long range) amphibious assault capability, as well as inherent humanitarian assistance/disaster relief and counter piracy capabilities.

The Yuzhao class vessels carry helicopters as well as two Russian-designed Zubr class cushioned landing ships, the largest military hovercraft of its kind.

However, after conflicts in Africa, the PLAN was unsatisfied with the firepower aboard the Yuzhao class and reportedly thought to create a new vessel, the Type 081 (pictured above).

Source: Congressional Research Service

Perhaps one of the more novel ideas being explored by the PLAN are very large floating sea bases. Only in the concept stage currently, these floating bases could host air strips, barracks, docks, helipads, or security bases across their massive proposed 2 mile long surface.

But experts on the topic speculate that these platforms would have ample peacetime uses, like supporting offshore oil rigs or even tourist destinations with duty-free shops.

Source: Congressional Research Service

The DoD cites Bill Gertz, writing for The Washington Times, as saying the following:

China’s military is developing electromagnetic pulse weapons that Beijing plans to use against US aircraft carriers in any future conflict over Taiwan, according to an intelligence report made public on Thursday [July 21].... The report, produced in 2005 and once labeled "secret," stated that Chinese military writings have discussed building low yield EMP warheads, but "it is not known whether [the Chinese] have actually done so."

China also possess a nuclear triad, or the ability to launch nuclear-armed warheads from submarines, land-bases silos, and bomber aircraft.

Source: Congressional Research Service

China's development and deployment of advanced and long range radars in the South China Sea is well documented.

The PLAN can use these sensors, which "reportedly include land-based over-the-horizon backscatter (OTH-B) radars, land-based over-the-horizon surface wave (OTH-SW) radars, electro-optical satellites, radar satellites, and seabed sonar networks," to guide their ballistic and cruise missiles, as well as more conventional forces.

Source: Congressional Research Service

China's military writing does not specify how they would use cyber warfare in a naval conflict, but it should be assumed that network warfare would be part of any sea battle. The PLAN is known to have invested heavily in cyber warfare.

Source: Congressional Research Service

Though the PLAN has made major strides towards modernization and world power status, they still lack in the following four key areas:

1. Joint operations with other parts of China’s military, 

2. Antisubmarine warfare,

3. Dependence on foreign suppliers for some ship components,

4. Long-range targeting.

Source: Congressional Research Service

The PLAN, as well as the other branches of China's massive military have made impressive progress in modernizing their forces, but they still lag behind in some key areas. 

The US Navy, unlike the PLAN, has commitments around the world. Currently two carrier strike groups are stationed in the Mediterranean as the fight against ISIS rages on and Russia continues to threaten NATO territory and personnel.

The US would face extreme difficulties in abandoning their posts worldwide to focus on the Pacific, whereas China would leverage every possible dimension of warfare (psychological, informational, legal, cyber, conventional, and possibly even nuclear or electromagnetic) to assert their dominance in their immediate region.

However the US has a built in advantage that the Chinese cannot hope to design or buy — alliances. Through the US's solid support of democratic and Western-leaning nations in the region, they have built a network of strong and determined allies that can band together against a rising authoritarian power like China.