Malcolm Turnbull has downplayed threats to national security from the Islamic State (IS) militant group, warning against turning the counter-terrorism debate into a "caricature".

The Communications Minister denied the comments were directed at Prime Minister Tony Abbott, who consistently refers to IS as a "death cult" and has warned Australians the group is "coming to get" them.

"The Prime Minister has been very measured in his comments on all these things as we all have," Mr Turnbull told reporters after his speech to the Sydney Institute.

In his prepared comments, Mr Turnbull said the danger posed by IS was not as grave as past threats to national security, such as Adolf Hitler.

"Now, just as it's important not to underestimate or be complacent about the national security threat from Daesh, it is equally important not to overestimate that threat," he said.

"Daesh is not Hitler's Germany, Tojo's Japan or Stalin's Russia.

"Its leaders dream that they, like the Arab armies of the seventh and eighth century, will sweep across Middle East into Europe itself. They predict that before long they will be stabling their horses in the Vatican.

"Well, Idi Amin wasn't the king of Scotland either. We should be careful not to say or do things which can be seen to add credibility to these delusions."

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Mr Turnbull said it was more important that counter-terrorism measures be effective than simply being tough.

"Tough policies can be popular — they may even be justified at the time they are conceived — but they can still be a mistake," he added, citing the 2003 United States invasion of Iraq as an example.

Laws which damaged individual freedoms played into terrorists' hands, Mr Turnbull argued.

"The Islamic terrorist seeks to provoke the state to overreact because it creates a more receptive environment for the extremists' recruiting efforts," he said, adding the Government had the right balance in its national security laws.

"It's important to remember too that people in societies with an equal determination to defeat terrorism, a current threat, can have different views on what is the right balance and indeed what the right measures are.

"Denouncing those who question the effectiveness of new national security measures as friends of terrorists is as stupid as describing those who advocate them as proto-fascists."

Cabinet leaks in May revealed Mr Abbott and a group of ministers including Mr Turnbull disagreed over a policy proposal to give the Immigration Minister the power to strip the citizenship of Australian nationals.

Last month the Government tabled legislation which would give the courts final say over whether dual nationals could be stripped of citizenship, the position Mr Turnbull argued for in Cabinet.

"We should always shudder a little, perhaps a lot, when cynics sneer at courts and laws as just troublesome obstacles standing in the way of justice," he said in his speech.