Yesterday I had a brief chat with Monash University terrorism specialist Andrew Zammit. For anyone interested in this topic, Andrew's blog is a must-read, and he is regularly sought out for comment and analysis by our major newspapers.

As you will hear, I talked to Andrew about ISIS and al Qaeda involvement in the Charlie Hebdo and kosher supermarket attacks in Paris; Andrew stresses that the two groups are not collaborating. I also ask Andrew about the claim that ISIS tends to be more focused on the Middle East while al Qaeda has stronger ambitions to attack the West (see Ahmed Rashid's latest essay for a deeper treatment of this issue) and the broader problem of fighters returning from the conflicts in Syria and Iraq. Andrew says that experience from Afghanistan suggests returning fighters are a long-term threat.