Right now the closest we can get to an actual war is probably with China due to the South China Sea dispute. When that happens, the victory will probably be ours since China dont get many friends in the region while the rest of the claimants got ASEAN.
Some might doubt that China will ever lose, but many historical defeats of the Chinese has proven otherwise. The worse outcome is probably a border war stalemate that the vietnamese and the indians had back in the past.
Still though anything can happen. If the USA and Australia decides to chip and aid us, it will be the opium war all over again only this time malaysia will be part of it.