The unprecedented blackout of front pages by Australia’s newspaper publishers this week is a highly significant event in Australian political and media history.

It represents the completion of a deep rupture in the relationship between government and media, which for many decades was marked by a preparedness on the part of the media to take notice of government advice where matters of national security were concerned.

It also represents the first concerted, unified, co-ordinated campaign by the Australian media – outside of wartime, when there were constant rows about censorship – to assert press freedom in the face of government oppression.

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It defies the prevailing political climate of fear created and sustained by both sides of politics since the terrorist attacks on New York and Washington on September 11 2001.

It defies the aggressive hostility towards the press shown by the federal government, with its determination to continue the prosecution of ABC and News Corp journalists for revealing government secrets that the public clearly had a right to know, and by the head of the Home Affairs Department, Mike Pezzullo, who says he wants people jailed if they leak government information to the media.

And it defies the contemptuous attitude to press freedom shown by the Australian Federal Police in raiding the ABC and the home of News Corp journalist Annika Smethurst over stories. This attitude was reinforced by new AFP commissioner Reece Kershaw, who told Senate estimates on October 21 that he had not turned his mind to the question of why the newspapers might have embarked on this campaign for press freedom.

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Those AFP raids led to two concurrent parliamentary inquiries, one by the Parliamentary Joint Committee on Intelligence and Security (PJCIS) and the other by the Senate Standing Committee on Environment and Communications.

The raids also galvanised the media industry. On June 26, the heads of all the main news organisations presented a united front at the National Press Club in accusing the government of criminalising journalism. They called for a thorough overhaul of laws on national security, government secrecy, whistleblower protection, freedom of information and defamation.

At the same time, they acknowledged the media had done a bad job of raising public awareness of the threat to press freedom. The “blackout” of October 21 was a dramatic first step in redressing this.

The involvement of News Corp, with its command of two-thirds of Australia’s daily newspaper circulation and its proven political clout, has given powerful impetus to the campaign. Whether it would have joined in had not one of its own journalists been raided is a matter on which Kershaw might care to reflect as he conducts his promised review of how the AFP handles these matters.

Meanwhile, Prime Minister Scott Morrison used Question Time in parliament to reassert his previous position that journalists are not above the law. His response ignored the fundamental point that the problem lies in the law itself.

There is a natural time frame for the media industry’s campaign. The PJCIS is due to report on November 28 this year and the Senate inquiry on March 16 2020. That gives the industry roughly five months in which to put enough political pressure on the government for it to make a serious attempt at law reform.

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However, the antagonism to this from the federal bureaucracy and the security services was revealed in their appearances at the PJCIS inquiry. They gave no ground at all. They regard the current regime of laws as right and necessary.

So, if the government does attempt genuine reform, it will face sustained opposition from its own public service. The government will also have to explain to the Australian people why the fear on which this whole politico-legal edifice has been built is no longer quite as acute as they have been led to believe.

It would also be turning its back on a history of government oppression of the media, a fixture in Australian political life that goes back at least as far as the earliest days of the Cold War.

The bugbear then was communism. ASIO kept files on Australian journalists whom it suspected – often on comically flimsy grounds – of being “reds”. ASIO then used these assessments to blight people’s careers by passing them on to media executives who were prepared to listen.

In those more quiescent days, the media were also prepared to be part of what was called the D-notice system, under which the media voluntarily agreed not to publish material on subjects defined in the D notices. These included material on atomic bomb testing in Australia, defence capabilities, and the whereabouts of Vladimir Petrov, a Soviet diplomat and spy in Canberra who defected with his wife in 1954.

The system lasted from 1952 to 1982, by which time the media had woken up to the fact that it was a betrayal of its public duty to collude with the government like this.

The old Fairfax newspapers in particular began to publish embarrassing leaks of intelligence material. Some of it showed how Australia was double-crossing Indonesia at a time when, publicly, Australia was doing its best to appease Jakarta.

The Sydney Morning Herald got out one such story on the front page of its first edition before an injunction was served in the middle of the night restraining it from further publication. The second edition of the paper appeared with a large white space where the story had been, carrying the word “censored” and recounting what had happened to the story readers were no longer allowed to see.

More spectacularly, Fairfax journalist Brian Toohey became the target of successive governments outraged over his stories based on leaks about intelligence activities. He became the bete noir of the then head of the Defence Department, Sir Arthur Tange. Toohey has now written a book called Secrets about the ways governments continually wage war against journalists and whistleblowers.

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In the recent PJCIS inquiry, the same Mike Pezzullo who said he wanted leakers sent to jail also proposed reviving the D-notice system. Given the current level of hostility between government and media, it seemed quixotic, to say the least.

However, it also showed that nothing changes in the culture and mindset of the Australian public service. The same instinctive resort to secrecy and control of information that has been its hallmark for decades remains its hallmark today. The only difference is that it has now been supercharged by the passage of 82 pieces of national security legislation since the September 11 terror attacks.