Every state and territory leader, plus the Leader of the Opposition, Bill Shorten, has nodded vigorously in agreement to the Turnbull government's new anti-terror measures, all of them eager to make public safety the supreme law. The changes announced yesterday by the Prime Minister infringe significantly on civil liberties and curtail traditional freedoms.

They may well be necessary but, other than the need to keep Australians safe, no explanation has been offered for this new clampdown. Safe from what, just now? Is the terror threat suddenly worse? Why else are the states falling in behind Canberra in lockstep?

Yesterday's special security meeting of the Council of Australian Governments agreed to three things: to allow authorities to hold terrorism suspects for up to 14 days without charge; to make available driver's licence photos to security agencies for identification purposes; and to broaden terrorism crimes to include hoaxes and the possession of terrorist instructional material.

Each may seem a minor advance on what already exists. The first, for example, will bring other states into line with NSW, which already allows suspects to be held for 14 days. The second is more substantial. It will allow real-time scanning of people in public spaces (entering Commonwealth Games stadiums on the Gold Coast, for example). But is it complete – or just another step towards something more comprehensive? The Prime Minister says about half the population has an identity photograph in a federal database.