Colin Freeman

Well, at their peak, it's thought that they had anything up to about 100,000 fighters in their old caliphate in Iraq and Syria, as well as franchises, operations that acted under their name.

These days, it's thought they have maybe no more than a couple of thousand fighters in Iraq and Syria, most of whom keep a fairly low profile as well.

They don't parade openly in the way that they used to.

So they're an absolute fraction of their original force.

Back in Australia, in addition to the investigation into the suspects, the country is pursuing even stricter gun control measures, including instituting a nationwide firearms registry and limiting the number of guns that one person can own.

That, of course, is All I Want for Christmas is You by Mariah Carey.