As could be expected, China and the United States are leading the charge. China's submarine fleet is expected to match that of the US by 2020 — in numbers, at least — with 78 subs. Many are to be stationed at the Yulin Naval Base along the southern coast of Hainan.
Despite continuing to increase its military budget every year, China's national defense spending still pales in comparison to the United States. The latest statistics from the Stockholm International Peace Research Institute say the United States remains by far the world's top military spender, with its US$665 billion defense budget equal to the total of the next seven countries behind it on the list. US military expenditure is still three times that of China, which is still considerable given the amount is equal to the aggregate spend of 24 countries in East and South Asia.
The US has also recently declared that it plans to deploy RQ-4 "Global Hawk" surveillance drones and F-35 fighter jets to the South China Sea to combat the PLA's aggressive posturing in the region through extensive land reclamation activities.
Vietnam, embroiled in a territorial dispute with China over the Paracel and Spratly island chain, recently made headlines for ordering six submarines from Russia as well as several surveillance aircraft. Vietnam's military expenditure has increased by 83% over the past five years, during which time its navy has also doubled its number of frigates to 68.
By contrast, the Philippines has only purchased a number of patrol boats from Japan, though it has increased military cooperation with the US by opening up its ports and bases to the US Navy.
As for other countries in and around the South China Sea, Indonesia has ordered three submarines from South Korea; Malaysia has ordered six patrol vessels from France and Singapore has acquired six Formidable-class frigates and ordered two new submarines from France to add to its current fleet of four.
Thailand, Indonesia and the Philippines are also said to have acquired new armored vehicles, helicopters and amphibious ships capable of surveillance and rescue missions.
The UK's IHS Janes Defence Weekly projects annual defense spending in Southeast Asia to reach US$52 billion by 2020, up from an expected US$42 billion this year. The 10 nations of Southeast Asia are expected to spend US$58 billion on new military hardware over the next five years, with naval procurements, specifically for the South China Sea, to comprise a significant portion.
The situation in the South China Sea may have even affected Japan, South Korea and India, each of which are making moves to bolster their respective navies. The Japan Maritime Self-Defense Force has increased 41 frigates to a total of 389. Tokyo has also bolstered defense spending to US$48 billion, which will include purchases of P-1 surveillane aircraft, stealth fighters and other US-made weaponry. South Korea, on the other hand, has added larger offensive submarines, while India is planning to build six new submarines.
Project 877E (Kilo class) submarine.