Over several years of Islamist extremist terror attacks in Europe a pattern of how events play out following these bloody incidents has emerged.

Typically, the attackers are known to the police, may well have served time in prison for criminal acts unrelated to terrorism, and may have been known for their sympathies to extremist ideology.

We have all been misled by the term ‘lone wolves’ into imagining that attackers are deranged, socially isolated people. In reality it’s more likely that attackers operate within a physical and virtual network of like-minded extremists.

In some cases, it emerges that there is a direct line of communication with extremists in the Middle East. The so-called Islamic State group was quick to claim responsibility for the Barcelona attack. We know from our experience of the thwarted attempt this July to put a bomb on an Etihad flight from Sydney that IS was directly involved, not simply ‘inspiring’ jihadists with their propaganda.

Another hallmark of IS’s bloody work is the attempt to stage multiple dispersed attacks in rapid sequence. Spanish police have confirmed that five suspected terrorists have been killed in Cambrils, southwest of Barcelona, blunting a second attack that could have been more devastating as the would-be attackers were wearing explosive suicide vests. In Alcanar, 200km south of Barcelona, police found 20 canisters of butane and propane gas in a house in which one person died and another was injured in an explosion said to be linked to preparations for the attack.

We will find out in the next few days how much of the familiar pattern has repeated itself in Spain. What we can already say with certainty is that IS has recently increased the priority for targeting that country. There has reportedly been an increase in the amount of IS propaganda translated into Spanish. There are approximately 150 Spanish fighters supporting IS in Syria, and Spanish authorities have been cracking down on Islamist extremist supporters. Around 180 alleged jihadist terrorists have been arrested in Spain since June 2015. In 2016 Spanish authorities disrupted ten terrorist plots and in 2017 uncovered at least two terrorist networks.

What broader conclusions can we draw about the IS attack in Spain? First, it’s clear that the terror group has decisively shifted its strategic focus from Iraq and Syria, where they are being hammered, to a distributed series of attacks in Europe and an attempted attack in Australia in July.

These are not random incidents perpetuated by unbalanced individuals. They are planned by IS in Syria, and, in the thwarted Australian plot, supplied with materials and advice on bomb making by the organisation.

We also know that IS draws on a network of supporters in many countries. Barcelona is home to a cabal of Islamist extremists who practise their ideology within a wider group of individuals who are at least prepared to tolerate this cancer within their community.

Add to that combustible mix the prospect or reality of IS fighters returning from the Middle East with a degree of competence in combat operations and a willingness to kill, if not die, for their ideology.

Speaking in Canberra yesterday [Friday] Prime Minister Malcolm Turnbull said that a study on protecting crowded places in Australia had been completed and will be released shortly. One outcome from that work will surely be the deployment of more vehicle obstructions around iconic gathering places, including many pedestrian malls. No city can be made fully secure from terrorist attack, but it is possible to sensibly strengthen key areas and Governments increasingly feel obliged to do so.

The unfolding tragedy in Spain casts a grim shadow over the ugly farce that took place in the Senate on Thursday when Pauline Hanson chose to extract some cheap theatre by wearing a burka into the Senate chamber.

In my view, Senate officials made an error by allowing her to enter the chamber. Their concern should not have been about an individual’s right to wear a certain type of clothing. The more fundamental issue, alluded to in an incandescent put down of Hanson by George Brandis, is the damaging propaganda value that IS and other extremist groups will extract from the images of Hanson in a burka.

Does anyone imagine that IS won’t be aware of that Senate performance and that they won’t use it to tell their supporters that our politicians were mocking their religion? Be assured that is precisely what IS will do, which could increase the risk of a terrorist incident in Australia.

Another consequence of Hanson’s actions is that it will act to further suppress interest on the part of some Muslim communities in Australia to help our police and intelligence agencies in monitoring our own Islamist extremists.

We should reflect that the key tip-off to trigger the police raids in Sydney in July came from allied intelligence, not our own grass-roots contacts. The houses raided and individuals taken into custody were, as always, well known to the authorities. But if we are to sustain our very good track record of thwarting terrorist plots, a positive working relationship with Muslim communities must be part of the approach. Hanson’s actions in the Senate spectacularly work against that national interest. Bollards may protect us from vehicles but they won’t protect us from our own stupidity.

The disruption of a sophisticated terrorist plot in Sydney is a clear demonstration that IS has the intent, means and support base to mount a terrorist attack in Australia. It’s inevitable that IS will try again, probably quite soon. That’s a reality that our security agencies understand very clearly.

Looking more broadly at Southeast Asia, it’s clear that the Philippines is emerging as the potential next front for IS, whose subsidiary Maute Group has controlled Marawi City in Mindanao Province for close to three months.

IS has capitalised on local grievances, but it is bringing its customary propaganda skills to bear, as well as making use of experienced fighters returning from the Middle East and recruiting locals. This is a seriously dangerous situation, not only for the Philippines, but also Indonesia and Malaysia. And it has the potential to directly threaten Australians and our interests in these countries.

The Turnbull government was right to deploy two P3 surveillance aircraft to assist the Philippines government in this fight. President Rodrigo Duterte is a complicated partner, but Australia’s interests are such that we need to do more to prevent IS from gaining a permanent foothold in the southern Philippines. Our government should look to substantially increase our support of the Philippines authorities by offering training and any other assistance that would lead to the decisive defeat of IS supporters in Marawi City. We also need to keep reinforcing the successes of our counter-terrorism cooperation with Indonesia, where the risk to Australians is potentially as great as during the early 2000’s and the attacks in Bali and Jakarta.