It looks like the US has just pulled Indonesia into South China Sea cooperation
“Indonesia also offered ‘closer cooperation with the US in economic and security matters through maritime policy, but not including accelerated ratification of the Indonesia–Vietnam Exclusive Economic Zone (EEZ) border. This [offer of closer economic and security cooperation] includes only export controls, increased military collaboration, the use of secure communications technology and strengthening border surveillance and control, particularly in the South China Sea.’ ”
“The document cited by IDN Times reveals that Washington sought two Indonesian commitments on the South China Sea in the trade agreement. First, it pushed Jakarta towards closer security cooperation, especially in the disputed area of the South China Sea. This closer cooperation presumably would include military exercises and joint patrols.”
“Second, the US wanted Indonesia to expedite ratification of the Indonesia–Vietnam Exclusive Economic Zone agreement. This is important because the maritime delimitation agreement signed by Indonesia and Vietnam overlaps with the nine-dash line that delineates China’s (ambiguous) claim to the South China Sea. Ratification of the agreement would reaffirm that Indonesia recognised no Chinese claim. It might also encourage Indonesia to back away from a November plan for joint development of the disputed waters in cooperation with China.”
Source: The Strategist – ASPI