The rest of us have realised that terrorism comes in many forms. At one end of the spectrum are large-scale, dramatic events planned over a long period and executed with ruthless efficiency by groups; at the other end, there are lone wolves of varying degrees of competence.

We cannot yet know everything that was known at the time about the perpetrator, but that will become clear. The review set up by the Prime Minister will also tell us the views different agencies had about this man's timein Australia.

Some have dismissed the perpetrator as a lone, disgruntled, alienated individual, as if that implies we ought not regard this as a terrorist attack. It seems to me that the people who, for example, decapitated a British soldier in the street could also be described as alienated and disgruntled, to say the least. Does it make it less of a terrorist attack because you are not taking instruction from another? In the Lindt cafe, I doubt that that distinction counted for much. Innocent people were taken at random into a siege scenario for a point to be made that in some way related to Islamic extremism.

From the outside, we could all take comfort in the calm and professional manner in which both NSW Police Commissioner Scipione and Deputy Commissioner Burn handled themselves and the media briefings. Ditto Prime Minister Abbott and NSW Premier Baird. The fact that there were no bombs discovered in other parts of the city and that this madman now appears to have acted alone in no way diminishes the leadership they showed. If they had said "Oh look, this is worrying, but he is a disturbed person acting alone so let's worry a bit less" there would have rightly been outrage. If it turned out the threats were correct, such casual early responses might have told us they were not up to the job. Criticism in hindsight is easy. Keeping calm and carrying on is not.

We should take a good look at ourselves after this nightmare. Why are so many drawn to watching coverage of something so horrific? More particularly, why were our TV screens filled with live coverage of the event as it unfolded?