The 2004 Boxing Day tsunami triggered an outpouring of grief and emotion as the scale of the devastation became clear.
It also triggered an unprecedented response from the federal government for aid and rebuilding efforts in Indonesia, as well as an opportunity to bolster ties with one of Australia's closest neighbours.
Federal cabinet papers from 2005 released by the National Archives showed the need for reconstruction assistance from the government to Indonesia represented a "potentially historic watershed" moment in the bilateral relationship.
Cabinet signed off in February for $1 billion to deliver relief and rehabilitation efforts in areas hardest hit by the tsunami in Indonesia such as Sumatra.
A cabinet minute from June of that year said efforts to help rebuild had "positioned Australia to advance its economic and security interests and to make a major contribution to Indonesia's development".
The tsunami also prompted concerns in cabinet about the government's own preparedness should a similar natural disaster hit Australia.
Cabinet was warned Australia had a limited tsunami warning system with coastal areas put at risk.
"The Australian Tsunami Alert System was not designed as an active tsunami monitoring and warning system," a submission from April said.
"Its capabilities are not sufficient to provide accurate, effective and timely warning of tsunami either on Australia's Indian or Pacific shores."
Australia would play a leading diplomatic role in joining with other nations in setting up an Indian Ocean warning system after the Boxing Day disaster.
While ties with Indonesia were improving following previous tensions relating to East Timor, there was concern in cabinet there would be limits on how much the Asian nation could properly crack down on terrorism or deliver economic reform.
The improved relationship with Indonesia would also be tested in 2005 by the high-profile arrests of Australians Schapelle Corby and the Bali Nine on drug charges.
A cabinet submission by then-foreign minister Alexander Downer said negative perceptions about Indonesia were a challenge after the arrests, and a proposed prisoner transfer agreement could alleviate community concerns.
Concerns were raised in cabinet about whether assistance with extradition and criminal investigations with countries that imposed the death penalty would undermine Australia's stance against capital punishment.
Cabinet noted law enforcement efforts with those countries had increased since the September 11 attacks and the 2002 Bali bombings.
A submission by then-attorney general Philip Ruddock noted helping countries in investigations where the death penalty was a punishment could have implications for consular assistance to Australians facing capital punishments.
"It is not inconsistent to provide international law enforcement co-operation to combat transnational crime and then lobby about the appropriateness of the penalty imposed," the submission said.
"Australia may shortly be in this position in the Bali Nine matter under the current policy of providing assistance."
Bali Nine ringleaders Andrew Chan and Myuran Sukumaran were sentenced to death for trying to smuggle more than eight kilograms of heroin out of Indonesia and were executed in 2015.
Cabinet papers also noted the government had been under fire for not providing enough support to Schapelle Corby after she was arrested for smuggling cannabis into Indonesia.
A briefing was also given by prime minister John Howard in October on terrorist attacks in Bali, which killed 20 people including four Australians.
The national security committee of cabinet said there had been issues for people in Bali trying to get through to emergency hotlines following the bombings.
