There are striking parallels between the Broken Hill massacre a century ago, and the recent Martin Place siege.
In both cases the media puzzled over the motivation of the attackers. The Barrier Miner wrote in 1915 “The question has been asked over and over again, and by many people since yesterday morning’s tragic occurrence, as to the motive of the men in attacking the picnic train with its load of women and children...”
The attackers in both cases had resided for many years in Australia and were well-known in their communities.
Both attacks were individual acts; although the 1915 attack by two individuals working together, they were not part of a larger network of jihadis, but were merely combining their individual efforts.
In both cases the attackers subscribed to the dogmas of jihad in the path of Allah, and martyrdom in Holy War.
In both cases, attackers were mobilized in response to a global call to jihad: in 1915 issued by the Ottoman Caliphate; in 2014 issued by Islamic State.
Both global calls to jihad had specifically invited Muslims around the world to commit individual acts of jihad by killing infidels (see here on the Islamic State’s call to Muslims to run over infidels with their cars).
In both cases the perpetrators had been experiencing difficulties with the law: in the 1915 massacre, Mullah Abdullah had been convicted days before for slaughtering sheep on an unlicensed premises. In the Martin Place siege, Hojat al-Islam Muhammad Hassan Manteqi (AKA ‘Sheikh’ Man Haron Monis) was facing criminal charges as an accessory to the murder of his ex-wife and had a history of convictions for serious offenses.
There were also similarities in the way the wider community and the media responded:
In both cases the media took pains to point out that the majority of people in the Muslim community abhorred the killings, and reported that no-one from the Muslim community wished to claim the bodies (see here and here).
In both cases there were no reprisals against Muslims.
However the Broken Hill German Club was burned down in 1915; the killings were considered to be linked to the World War I conflict as a whole, rather than as manifestations of individual jihadism.
http://www.meforum.org/4947/one-hundred-years-of-jihad-in-australia
The key is, insufficient response from the rest of society, or more accurately, THE society failed to act appropriately against the anti-social group.