Australia and Indonesia have avoided a submarine arms race as a benefit of Australia's haphazard submarine acquisition habits.
Australia's 2009 Defence White Paper set a requirement for 12 new SSKs. In 2014 they were to be Japanese Soryu variants. Then in 2016 policy
changed to 12 very large, tailor made, Naval Group designed Attack-class subs.
Then in 2021 policy changed to US and then UK SSNs under AUKUS.
In response many in the Indonesian defence establishment advocated
12 new SSKs for Indonesia to match Australia's 12. As Australian plans fell apart Indonesia has decided not to allocate sufficient funding for 8
or 9 new SSKs to make 12. 12 has effectively become a force of 4 x Type 209
variants, including one 43 year old Cackra-class and three new Nagapasa-class.
In 2019 Indonesia pencilled in a contract to buy 3 x additional
Nagapasas. But with Australia’s 2021 cancelation of the 12 x Attack-class SSKs this
removed any arms race pressure for additional Nagapasas. So Indonesia suspended that 2019 contract.
Indonesia is now, probably tentatively, considering renewing
the Nagapasa contract OR (as this report indicates) buying Scorpenes OR buying AIP equipped
Type 212s or 214s.
Indonesia might also be calculating (or hoping) that Australia’s quest for SSNs, under AUKUS, won’t amount to anything until the 2040s (ie. no US Virginias for Australia in the 2030s).