The barbarians of so-called Islamic State are succeeding in inspiring acts of deadly violence in a lengthening list of countries, including Western ones.
Last year it was Canada and Australia. Last month it was France. Last weekend it was Denmark.
And last week Australia was to suffer a second attack, but for the quick work of the NSW police in intercepting two young Sydney men allegedly planning an imminent attack.
The coalition forces in Iraq are killing large numbers of the barbarians, yet new recruits still travel to join the fight.
In the countries with the best living conditions on the planet, freshly radicalised citizens are taking to killing their fellow citizens.
This is clear evidence that Islamic States' propaganda effort is working. The barbarians put tremendous effort into their propaganda.
According to a senior Australian official, the IS movement pumps out 90,000 to 100,000 social media messages per day. That's right, per day, in a wide array of languages.
The group has a centralised media centre. There has been much comment on the increasing care and effort that goes into the atrocity videos it produces.
The civilised world has failed to defeat the appeal of one of the most unimaginably brutal organisations on the planet.
But the numbers of people they kill in the Western world is relatively small. In France it was 12. In Demark two. In Australia Monis killed either one or two, depending on the outcome of the final investigation.
The would-be Sydney attackers last week, armed with a knife and a machete, appear to have been intending a similarly small death toll.
Is this some small consolation? Of course. But killing large numbers is not the chief aim of the terrorists. It is not the metric by which they measure success.
"Terrorists want a lot of people watching, not a lot of people dead," a US expert on the subject, Brian Jenkins, remarked in 1998.
Monis took his hostages in the Lindt café not because it was next to the Reserve Bank but because it was opposite the headquarters of Channel 7.
The publicity is the point. It is about violence, but it is just as much about show business.
This is how they get their existential lifeblood – attention. This is the source of their power, their command over the public mind. This is how they excite those vulnerable to their message, and how they spread fear among the population at large.
The barbarians put on the show and, according to a former deputy chief of counterterrorism at the CIA, Paul Pillar, "We, the public, and the media have responded by being duly fascinated and horrified.
"This is one of the ways, though not the only one, in which we have been playing into the hands of ISIS," he wrote last October in a piece titled Forgotten Lessons of Counterterrorism.
"We also serve the group's objectives every time we (including our government or the press) portray the group as ten feet tall and strong enough to warrant something akin to a declaration of war."
We do it every time we describe one of their pathetic online rantings as "chilling". They're not chilling unless we allow them to be.
We do it every time we call them by the name they have chosen for themselves – Islamic State, for a group that is neither. "The press does not necessarily refer to other entities by their preferred but non-descriptive names (how many newspaper articles about North Korea do you see that identify it as the Democratic People's Republic of Korea?); why should it do so with this one?" poses Pillar.
This newspaper, among many others, is guilty as charged.
Tony Abbott needs to be careful in the way he responds to the threat, too. After the two Sydney men were arrested last week before they could kill anyone or release their prerecorded video message, Abbott took to the microphone to read out their threatening message. Was it really wise for the Prime Minister to dignify and disseminate their message of hate for them?
The barbarians are winning the propaganda war. We have been handing them victory. The forces of civilisation need to be more mindful of the way we respond to the barbarians. We need to stop giving them exactly what they want.
One smart response to the atrocity videos is the one suggested last week by Gillian Tett, a columnist with London's Financial Times – stop watching.
"The fastest way to rob these videos of their power is to respond with a cultural counter-fight and stop watching.
"We can all stage our cultural counter-insurgency too by refusing to click on violent images such as the brutal killing of Jordanian pilot Muath al-Kasabeh."
As a Durham University anthropologist, Frances Larson, says: "There is no triumph in the killer's actions until we watch. Modern technology may offer a hiding place to voyeurs but it can also give a voice to human decency."
The governments of the coalition nations are about to counter the barbarians' propaganda with propaganda of their own.
The first phase of the kinetic fightback against the barbarians is well under way. But the propaganda fightback has yet to begin.
As Barack Obama's special envoy to the counter-IS coalition, John Allen, tells Fairfax Media:
"The attractiveness of Daesh," he says, using the group's Arabic acronym, "has often been best communicated through… social media. Part of the societal outreach is to try to get them off those sites, to deglamourise that message that seems to be a message of omnipotence, a message of power, a message that seems to be conveyed through horrific acts that Daesh perpetrates on the subjugated populations."
Governments will pool resources to track and to counter the barbarians' social media channels, he says.
"The best way is to have a countervailing message that is superior or more resonant. Also to convince those kids to get off those sites.
"Daesh," says Allen, "will not be fully remedied until we kill the idea of Daesh, and that's in the information sphere."
And that is a sphere in which we all operate. The authorities' plan may work, and may not. But every citizen has the power to grant the barbarians power over our society. Or not.
Peter Hartcher is international editor. Sydney Morning Herald