However, the announcement reflects ASIO's assessment that we now have a less dangerous terrorism threat environment in Australia given the low level of terrorism-related activity over the past year and foreseeably looking forward to next year.

How does this assessment compare with the terrorism risk assessments of our Five-Eyes partners?

The US and UK have higher international profiles and would presumably be more at risk from terrorism than Australia, Canada, and New Zealand.

The US Department of Homeland Security does not use threat levels and instead puts out regular bulletins describing the current threat; the next one is due out on Wednesday.

The UK has five levels - "Low", "Moderate", "Substantial", "Severe", and "Critical". The UK is at "Substantial".

Canada has five levels - "Very Low", "Low", "Medium", "High", and "Critical". Canada is at "Medium".

New Zealand has five levels - "Very Low", "Low", "Medium", "High" and "Extreme". New Zealand is at "Medium".

Australia is the only Five-Eyes country at the second-lowest level of threat.

Threat by the way is a factor of "Capability" and "Intent". A terror group may have the capability to mount attacks but lack intent - or have intent but lack capability. When it has both intent and capability you have a problem.

ASIO does not discount the possibility of attacks by radicalised individuals that can be mounted at short notice using readily accessible means, such as knives and vehicles. These are the kinds of attacks still encouraged by Islamic State.

Since 9/11 the main concerns in Australia had been attacks by local Islamist extremists encouraged by Al-Qaeda and Islamic State. These terrorist groups still operate in hotspots in Africa and Asia but are seen as having less influence in Australia now than they had in the past.

Nevertheless, some Australian migrant communities are clearly worried about Islamic State wives and children from Syria being resettled in their areas. This is understandable given that some communities contain families who fled Islamic State's murderous rampage in Iraq and Syria and may have had family members killed by the group.

MORE OPINION:

Looking forward, terrorists who rely on knives and vehicles are going to be less of a concern than groups that could have access to firearms and explosives.

Fortunately, Islamist extremists in Australia have had trouble accessing firearms, particularly semi-automatic weapons such as the L1A1 Self-Loading Rifle (SLR), formerly issued to the Australian Army). The same is true of access to precursor chemicals that can be used to make "improvised explosive devices" or IEDs.

ASIO, the AFP and state police have all done a good job of preventing Islamist terrorist attacks in Australia since 9/11. Over the past eight years, 21 significant plots have been detected and disrupted.

More recently, security concern has swung to the terrorism threat from right-wing extremist groups. Three of them are now listed by Australia as terrorist organisations: Sonnenkrieg Division (listed August 11, 2021); The Base (listed December 10, 2021); and National Socialist Order (listed February 18, 2022).

Firearms access may be less of a problem for right-wing extremists who are more likely to belong to gun clubs, bikie gangs, and have access to firearms in the grey market of undeclared weapons.

The far-right threat posed by firearms access was clearly demonstrated by Behring Breivik's attack in Norway in 2011 that killed 77 people (eight by bombing and 69 by shooting), the Brenton Tarrant shooting attack in New Zealand in 2019 that killed 51 people, and the numerous far-right shootings in the US since 9/11.

In Australia there were 3.2 million civilian registered firearms before the 1996 Port Arthur massacre that resulted in the death of 35 people. The shooter, mentally disordered Martin Bryant, used an SLR and Colt AR-15, both semi-automatic weapons. The subsequent gun buyback scheme reduced the number of civilian-held firearms to 2.5 million, but the total has since increased to approximately 3.5 million civilian-registered firearms and an estimated 260,000 unregistered weapons.

We have been fortunate not to have had a mass casualty terrorist attack in Australia but should be mindful that Brenton Tarrant was an Australian and his lethal attack could have taken place in Australia. On the plus side for ASIO, right-wing extremist groups should be easier to penetrate and monitor than Islamist ones.

So far there has not been any violent spillover in Australia from ethnic/religious-based conflicts in Turkey, Ukraine, Israel/Palestine, Afghanistan, and Xinjiang, but it remains a possibility.