Nor is this mine the only challenge facing the Save the Tarkine group. Its victory in the Melbourne hearing is over only one of a long list of mining and logging proposals for the rainforest region in the state's remote northwest.
Ten new mines are planned in the Tarkine over the next five years, nine of them open-cut.
Almost 60 exploration licences have been granted.
Less than 5 per cent of the 470,000sq km area is protected despite efforts to declare the region a national and world heritage area, and logging also now extends through much of the region, including clear-felling of old-growth eucalypt forest and myrtle rainforest for woodchipping.
The Tarkine is home to more than 60 rare, threatened and endangered species, including the world's largest freshwater lobster, the Tasmanian wedge-tailed eagle - and the devil, a squat, black carnivorous marsupial with a chilling call and one of the strongest bites per unit body mass of any mammal predator.
Hunted almost to extinction on the island until becoming protected in 1941, devils are now endangered throughout most of Tasmania.
Most are ravaged by the facial tumour disease, transmitted by bites, which kills up to 90 per cent of adults in highly concentrated populations, and about half in medium- to low-density colonies.
This is why the Tarkine is so important. The region's devils are the last living free of the disease.
But jobs and investment are desperately needed in Tasmania. Its economy lags well behind the rest of Australia and its unemployment is the country's highest, reaching 8.9 per cent in June.
And of all regions, the northwest - where Shree Minerals planned its A$20 million mine - is the worst-hit. The mine would have created 120 jobs and generated up to A$80 million ($92.9 million) a year.
Last December Butler's predecessor, Tony Burke, approved the mine near Temma, on the island's west coast, subject to 30 conditions - including that Shree give A$350,000 to efforts to save the devil.
This was not enough for the Save the Tarkine group. It claimed Burke had not acted in accordance with federal environmental protection and diversity legislation requiring a full assessment of developments that could harm endangered species.
The devil is fully protected under federal legislation.
While rejecting the bulk of the group's claims, Justice Shane Marshall found Burke had failed to properly consider advice about the devil.
Tasmanian Premier Lara Giddings urged action to restore approval for the mine.
"We see it as economically sustainable, environmental sustainable and an important investment that will help create jobs in the mining industry," she said.
Butler will now review the court's decision.