Military build-up in Southeast Asia has been a noticeable trend, as shown by force modernization, although there is not necessarily political will to improve military effectiveness. The phenomenon has been attributed to various factors, including protecting economic interest, self-reliance in the reduction of US commitment in the region, domestic and foreign tensions, and the need to replace colonial era material, but also some non-military related factors such as national prestige, political corruption, etc. Almost all Southeast Asian nations modernized their militaries since 1975, the ending year of the Vietnam War, and continued since then, even though the process was slowed after the 1997 Asian financial crisis. During this period, military personnel, tanks, armored personnel carriers (APCs), medium-range howitzers, missile-armed naval vessels, combat helicopters and combat aircraft increased and modernized. However, experts pointed out that this still did not fit the definition of an arms race. Southeast Asia had seen an increase in absolute defense spending, the biggest increase compared to other regions of the world, even though they are relatively unchanged in proportion to the country's GDP. The South China Sea dispute was cited by some analysts as the motive, but others pointed to steady military expenditure per capita and relatively small in change of military inventory compared to old equipment replaced. Statistics Regional overview Noticeable modernization trends in Southeast Asia are acquiring of technological sophistication, such as guided munitions, and investment in command, control, communications and computer processing, as well as intelligence, surveillance, reconnaissance systems (C4ISR). Multi-role fighter aircraft, maritime reconnaissance aircraft, modern missiles (including anti-ship missiles, beyond visual range air-to-air missiles, air-to-ground missiles, tactical ground-to-ground missiles), modern artillery systems, submarines and warships equipped with the new electronics and anti-ship missiles, including Scud missiles, late-model MiG 29, F16, F18 and Su27 jet fighters, MRLS systems, and modern frigates armed with Harpoon and Exocet missiles became more widespread. However, any regional nation seem not to be able to adopt Revolution in military affairs (RMA) due to lack of military resource, technology and armed force specialist. Almost every military increased its conventional capabilities, while archipelago nations adopted rapid deployment. Navies tend to cover its lack of mine counter-measures, maritime surveillance, offshore patrol and anti-submarine capabilities. Another notable trend is to acquire advanced fighters, with Singapore being the first to introduce fourth-generation jet fighters. Southeast Asia was the fastest-growing military spending region in the world between 2009 and 2018. Between 2009 and