The alleged plot to behead a random Sydney person is chilling, but equally worrying is the way social media is being used to promote terrorism. Perhaps we are in a new era of crowdsourced terrorism, writes David Malet.

The latest alleged terrorism plot against Sydney should provide all Australians with evidence of three things: that the nation is indeed the Lucky Country and not one that is "safe" by virtue of geographic isolation; that there is and has long been a very real threat of violence by disaffected individual Muslims; and, most importantly, that far more members of the Australian Muslim community deserve the public's gratitude for dobbing in family and friends instead of keeping quiet as many others would.

But it also raises the question of whether we are prepared for terrorists who do not collaborate with others, "lone wolves" who don't give away their intent. If community reporting and good police work have prevented attacks, it is only because there have been leads to follow on big plots.

What happens when there is no warning because plotters are working alone?

The question is difficult to answer because the rules of the game have changed very recently. In the 1970s, when foreign nationalist extremist groups were setting off bombs in Sydney, the conventional wisdom was that terrorists don't want people dead, they want people watching.

Terrorism groups used violence to call attention to themselves and their pet causes, but they followed the strategy of what they thought was just enough to get attention and typically avoided extreme brutality that would turn the public against them.

In the decade from the mid-1990s, in the face of indiscriminate attacks against large numbers of civilians in the name of religion, the thinking changed.

Bali, 9/11, the nerve gas attack on the Tokyo subway, and multiple unsuccessful plots to attack Sydney demonstrated that a new breed of apocalyptic terrorists who believe themselves answerable only to their god now preferred to have people dead, and terrorism networks would plot large-scale attacks in secret.

Today it appears that terrorists now want people dead and people watching. Over the past several years, social media has offered the opportunity to find like-minded people around the world, without the editorial filter of traditional news.

By 2009, when Australian citizens who had gone to fight with Al Shabaab in Somalia returned to plot an attack, other Westerners in Somalia were posting jihad rap videos on YouTube to try to get sympathetic viewers to join them.

They were not trying to persuade everyone to their cause, just the like-minded who wanted proof that violence could empower them if they joined the movement. Atrocity videos also draw curious viewers who can then be contacted and ultimately persuaded to become foreign fighters.

If there is any positive side to this development, it is that lone wolf terrorists have the same need of attention, and so they have been turning to social media as well. This is a positive development because internet activity can be monitored for content and also for personal or virtual connections.

Previously, a lone wolf like the Unabomber in the United States could go nearly 20 years without being caught because he left no leads for a long time.

Today, lone wolves like Norway's Anders Breivik and small cells like the Tsarnaev brothers in Boston have made extensive use of social media postings before committing violence. In these cases, the names are familiar to us because they were not stopped in time.

But others have been, and their online postings have led the way to them.

But there is a greater danger from the technology that might soon outweigh this advantage. Lone wolves are rarely alone these days when they can go online and find others around the world to urge them on to enjoy their 15 minutes of fame for what they see as a just cause against oppression. Because they operate on a small scale, they generally cannot inflict mass loss of life the way that organised terrorism groups can (Breivik and right wing American bomber Tim McVeigh were exceptions).

Their danger has been in their apparent unpredictability due to lack of monitored chatter. Now, however, even small scale attacks - the murder of a single victim - can reverberate around the world whether from Syria or from South Australia.

Simply using the name Islamic State is guaranteed to get attention, and the gruesome act of cruelty depicted in decapitation videos carries enough shock to ensure that everyone pays attention, at least for a time. No grand plots are needed.

Rather than lone wolf terrorism, perhaps we are in a new era of crowdsourced terrorism.

Dr David Malet is senior lecturer in International Relations at the University of Melbourne and previously served as Director of the Center for the Study of Homeland Security at Colorado State University. View his full profile here.