Israel’s media operate under official censorship. That has been a fact of my professional life as a journalist covering foreign policy and national security. Here’s how it works: any story involving defence, intelligence or nuclear matters must be submitted to the military censor’s office. It can run only after being stamped for approval.

Israel being Israel, and not China or the former East Germany, its censorship is less scary than it might appear. The 35 military censors are not faceless bureaucrats. You know them personally and can negotiate wording to let the story pass.

Paradoxically, the existence of censorship has its advantages. Military and intelligence sources are more likely to give you secret information, trusting the censor to play bad cop. And once you have submitted anything to the censor, you’re relieved of legal responsibility. The main goal of censorship is deterrence: you know that your story will be blacked out, so why bother writing it. All of us are well-trained in self-censorship and in using code words such as “nuclear capability” or “nuclear option” rather than “nuclear weapons”.

The success of censorship relies not on coercion, but on public support. The military and intelligence community enjoys sacred status in Israeli society, and “national security” resonates much better than “civil liberties”. Many journalists accept censorship willingly, and criticise their peers who break with the official line. They are even proud of knowing the story and withholding it. As a young journalist in the late 1980s I prepared a critical story about the Mossad. “Do it in your free time, it’ll never see the light of day anyway,” my editor warned me. It was duly censored. My new editor, Meir Schnitzer, appealed to the high court. We won a landmark case which set the scope of censorship.

Since then, the tide of censorship has turned in tandem with the public sentiment towards security. The second Lebanon war of 2006 caused a major setback, as the media were blamed for disclosing the locations of rocket attacks and thus “supplying Hezbollah with targeting data”. The Olmert government, and the Netanyahu government that succeeded it in 2009, leveraged the public anger to impose stricter censorship.

In most cases the media live with restrictions through quoting “foreign sources”. At Haaretz we can’t write that Israel bombed a nuclear reactor or arms convoy in Syria, but if it’s published in a London-based newspaper it’s fine.

Last week, however, we were told not to even quote foreign sources, when Australia’s ABC news broke the story of Ben Zygier, an Australian-born Mossad agent who had strayed from his mission, was locked secretly in solitary confinement and committed suicide in prison in 2010. The affair was covered by a gag order, which is stronger than ordinary censorship: disobeying it risks criminal prosecution. We ran a story quoting the broadcast, and were told to take it off our website. Then the editors of Israel’s newspapers, TV and radio news channels were summoned to a private briefing by the Mossad head, Tamir Pardo, who asked them to ignore the story.

I refused to attend. I don’t want to know more than my readers. In the meantime, the Facebook and Twitter feeds of thousands of Israelis were filled with links to the ABC news story. And three courageous opposition Knesset members asked the justice minister, on live broadcast, about the mistreatment of a mysterious prisoner. Several hours later, the gag order collapsed, and the government issued an official statement the next day, acknowledging “negligence” in the treatment of Prisoner X.

An overdue debate over the mishaps of the Mossad and the prison service ensued. Luckily, our Australian colleagues helped to strengthen Israeli democracy. But unfortunately, as long as “state security” is sacred in the public mind, we will have censorship.

Aluf Benn is the editor-in-chief of Haaretz