Prime Minister Malcolm Turnbull agrees with his British counterpart, Theresa May, that enough is enough.
"This is a corruption, a disease within Islam. We will never give into terrorism, we will never change the way we live. We defy these cowardly criminals. We defy them and we reject the poisonous ideology that they peddle."
Mr Turnbull says the internet has been fertile ground for that I-S ideology.
"There is too much tolerance of extremist material on social media and that, ultimately, requires cooperation from the big social media platforms: in particular, Facebook and Twitter."
But former Prime Minister, Tony Abbott, says political correctness is leading to a wider tolerance of what he calls radical Islamist views.
Mr Abbott claims Australia's leadership suffers from 'a surrender mindset' which weakens defences against terrorism.
"There is this notion that Islamophobia is almost as big a problem as Islamist terrorism. Well, Islamophobia hasn't killed anyone. Islamist terrorism has now killed tens of thousands of people: that's why it's absolutely critical that there be the strongest possible response at every level."
During his time as Prime Minister, Mr Abbott put a commando unit on standby during the Lindt cafe siege in December 2014.
He wants to amend the Defence Act to allow specialist army units to take the lead on major domestic terror incidents.
The former Prime Minister says there also needs to be more clarity for Australian police to give them the authority to shoot-to-kill terrorists.
"These people have this 'death to the infidel' approach and such sieges are almost inevitably going to end badly so the sooner they're ended by the police or other agencies the better."
Islamaphobia was blamed for two recent deaths in the United States, and for the 2011 massacre in Norway.
Kuranda Seyit, from the Forum on Australia's Islamic Relations, says by alienating the Muslim community you're letting the extremists win.
"Terrorism is a criminal act. It has no religious affiliation and it doesn't matter which religion the person is from and whatever motivation they have, it's a criminal act. We can't affiliate Islam with terrorism because we've seen it before - we've seen it with Christian organisations and white supremacists."
The rapid response of British police to the London attack is being applauded.
Prime Minister Turnbull says Australian police also have clarity when responding to particular types of terrorism attacks.
"The practice of cordon and contain, which had been used for many years, is not applied by police in situations where there is an active armed offender, an active shooter or someone with a knife, such as you saw in London."
