TAIPEI, Taiwan — Chinese military modernization and behavior in the South China Sea and East China Sea has forced its regional neighbors to gear up for what could be a nasty war in the not too distant future.

The big four — Japan, South Korea, Singapore and Taiwan — are the primary defense spenders in the region with total defense spending and annual budgets for personnel, operations and procurement ranging from a low of $9.4 billion for Singapore and $9.8 billion for Taiwan to about $35 billion and $40 billion for South Korea and Japan, respectively.

Countries such as Indonesia, the Philippines, Thailand and Vietnam fall significantly below that amount in the $4-6 billion range and are unable to procure large quantities of modern weapon systems. They are also far less likely to be able to operate and integrate advanced weapon systems into their force structure due to poor training, corruption and poverty, and most have a history of procuring cheap Russian equipment with a poor record of quality assurance and logistical and maintenance support.

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Japan, South Korea and Taiwan are all concerned by the ballistic and cruise missile capabilities of either China, North Korea or both. In response, three three nations have improved their missile defense capabilities — with the procurement of Patriot Advanced Capability-3 ballistic missile defense systems for Japan and Taiwan, and the Terminal High Altitude Area Defense for South Korea. Singapore largely focuses on short- to medium-range air defense procurements, as there is no significant missile threat from its neighbors.

This includes sea-based anti-ballistic missile systems, said Bob Nugent, a consultant at AMI International. Japan and Korea will continue to weigh investments in the Aegis Combat System for their destroyers, while maintaining enough subsurface capability to provide the current level of deterrence. "Developing a submarine-launched land-attack capability would leverage the strategic impact of their sub force even more," he said.

Singapore technically has no serious security concerns from China, "preferring to cloak its security policy in such ambiguous terms as ‘regional stability and peace,’ or ‘fighting terrorism,’ " said Richard Bitzinger, a senior fellow and coordinator of the Singapore-based Military Transformations Program at the S. Rajaratnam School of International Studies.

Indeed, Nugent said Singapore has a "poison shrimp" strategy designed to make it too painful to swallow. This is evident by Singapore’s impressive lineup of aircraft and naval platforms, including three fighter squadrons of F-15s and three squadrons of F-16s, and a navy consisting of frigates and submarines. Singapore is looking closely at improving its C4ISR and cyber capabilities, along with the navy looking at whether it should procure 4000-ton frigates, he said.

All four countries have a strong interest in procuring fifth-generation stealth fighter aircraft, either by developing an indigenous stealthy fighter, such as the Korean KF-X and Japan’s X-2 Shinshin, or buying the Lockheed Martin F-35 Lightning. Singapore, Korea and Japan have all been offered the F-35 option, but Taiwan has not been given the choice due largely to political problems between Beijing and Washington. China has called any future sales of advanced fighter aircraft, whether it is the F-16C/D or the F-35, a red line.  

Other potential buys? Japan, South Korea and Singapore have expressed interest in the Bell Boeing V-22 Osprey capable of vertical takeoff and landing (VTOL). The VTOL capability gives these countries significant options to continue operations after air bases are destroyed by ballistic missiles and air-to-ground bombs. VTOL capabilities also factor into the Big Four’s interest in the F-35B variant for the same reason, particularly Taiwan since it faces a ballistic missile threat numbering around 1,300 Chinese ballistic missiles.

Nugent said AMI’s profile of the Big Four’s navies, looking at budgets, budget share, force structure and personnel, divides them into two groups. Japan's and South Korea’s navies are regional forces with considerable capability to deploy and operate globally, centered in their large multipurpose aviation capabilities, amphibious warships and Aegis-equipped surface combatants. Both have balanced force structures, with modern capabilities in the submarine, surface and air domains, as well as robust potential over land capability, such as the South Korean Marine Corps. South Korea’s naval structure is driven by North Korea, but also other regional threats, such as China and Russia. Japan, traditionally centered on countering the Russian threat, is now displaced by the China threat.

Bitzinger said that Japan would continue to focus on China's ability to challenge Japanese military power in the East China Sea, particularly the competing claims over the Senkaku Islands. 

It is responding by building up its submarine force, and its ability to engage in power projection, particularly its growing fleet of helicopter destroyers — Izumo- and Hyuga-class.

It is also upgrading its maritime patrol aircraft assets with the indigenously produced P-1 Maritime Patrol Aircraft.

Taiwan and Singapore are much more local forces, Nugent said, with naval structures centered on specific mission sets. In Taiwan's case it is clearly an extension of the national homeland defense mission against China. Singapore's Navy is designed to contribute to the deterrence or poison shrimp strategy against would-be large nation aggressors using its submarine force, while having the forces to execute maritime security missions in the South China Sea and Straits of Malacca.

The other strategic driver of future maritime requirements for the four countries has been the United States' relative decline in capability in numbers of ships, aircraft and personnel — notably anti-submarine warfare and anti-surface warfare in the Asia-Pacific region — over the past 15 years, or essentially since 9/11.

"Which means that all four navies, in greater or lesser degree, must invest to maintain balance in their fleets across all the domains, while acquiring some of the capabilities, such as logistics, C4ISR and unmanned craft that traditionally have been provided by US," Nugent said.