Mr Turnbull said Islamic State was "not Hitler's Germany, Tojo's Japan or Stalin's Russia''. Credit:Reuters "Just as it is 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, using an alternative name for Islamic State. He said Islamic State was "not Hitler's Germany, Tojo's Japan or Stalin's Russia" and despite the terror group's own aspirations to world domination, "we should be careful not to say or do things which can be seen to add credibility to those delusions". The speech stands in obvious contrast to the tone struck by Mr Abbott in recent weeks, when the Prime Minister has said Islamic State is "coming after us" and "coming … for every person and every government". In a carefully worded plea for calm debate over national security, Mr Turnbull said people who equally opposed terrorism could have different views on the right balance between security and liberties, according to speech notes provided by his office.

"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'." Mr Turnbull also effectively confirmed his opposition to Immigration Minister Peter Dutton's original proposal for ministerial discretion in stripping citizenship from terrorists, which Mr Abbott reportedly backed. He noted that "instead of proceeding with a proposal which would give the minister the discretion to revoke Australian citizenship if he believed the person affected had engaged in terrorist activities", the revised proposals would build on existing law that strips citizenship from people who fight against Australia with foreign militaries. Mr Abbott lashed out at the opposition in the heat of the citizenship debate, accusing shadow attorney-general Mark Dreyfus of wanting to "roll out the red carpet" to terrorists after Mr Dreyfus suggested Australian jihadists abroad should be brought home to be prosecuted. Mr Turnbull said laws should be updated, particularly as technology changed, but stressed this must involve "respect for the rule of law" through involvement of the courts, an apparent veiled criticism of Mr Dutton's early proposal.

He also said the government had so far got the balance right between security and liberties but urged that "in order to ensure we continue to do so, this conversation is one that should proceed in a considered manner respectful of the views and experience of others". In other remarks, Mr Turnbull said few people today believed that the 2003 invasion of Iraq was "not a tragic error". "It is more important that counter-terrorism measures be the right ones, the effective ones, than that they simply be 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 said. "I suppose there is nothing tougher than invading a country, overthrowing its government and occupying its territory. But with the benefit of hindsight, few today contend that the 2003 invasion of Iraq, popular with the US public and the Congress at the time, was not a tragic error." Follow us on Twitter