No, the great majority of the disruption is caused by overreacting to the very minor threat posed by terrorists. To be fair, Tony Abbott appears to realise this, which is why he has called for people to go about their usual business, but clearly the right hand of government is not speaking to the left hand, which is intent on creating as much havoc and disruption as possible and therefore allowing the terrorists to win.
And we haven’t even got to the aftermath of all the hideous legislation, spending bills, etc. that will undoubtedly be passed in the wake of this incident, further cementing the terrorist’s victory. Of course the incumbent government will find the incident a useful catalyst for bolstering its support and pursuing its own priorities, as it and other governments have in the past. In that sense you could say that the terrorist phenomenon considered as a whole is actually a mutually beneficial partnership between terrorists, media organisations, and governments – which is why it continues to enjoy such a high profile in the public consciousness, all rational assessments to the contrary.