Thankyou readers, but, I can't begin to answer the 40+ comments received since Australia's September 16, 2021 AUKUS Australian SSN decision. I invite readers to argue among yourselves in Comments.
Instead I'll write extra articles that need to be raised about this vast subject. This is beginning with SSN arms race possibilities. This may link an Indonesian SSN program with Russia and/or South Korea.
Indonesia has always been sensitive to its near southern neighbour Australia's arms acquisitions and resulting defence capabilities. This is particularly in terms of conventional subs (SSKs). Once Australia expressed a 2009 White Paper intention to build 12 large SSKs significant factions in Indonesia's Navy and military-industrial-political complex began advocating a 12 Indonesian SSK navy to match.
Now some Indonesian factions are advocating Indonesian nuclear submarines. Russia, a past (submarine) and current (jet fighter) arms supplier to Indonesia, might assist in an Indonesian SSN project.
South Korea, Indonesia's current SSK supplier, has sufficient nuclear technology and broached intentions to build SSBNs. In a joint South Korean-Indonesian project SSNs for both the South Korean Navy and Indonesia Navy could eventually be produced. The US (now permitting Australia to have nuclear propelled subs) can no longer ban US ally South Korea (on non-proliferation grounds) from using nuclear propulsion for submarines.
Catastrophic Indonesian submarine accidents, seen lately with KRI Nanggala, are a worry. Indonesia being in the land (and at sea) nuclear facility threatening "Pacific Ring of Fire" is cause for concern that increases even unintentional dangers of a future Indonesian SSN. That may all increase risks of a regional, radiation, environmental, disaster, that could also impact Australian waters.