Documents from the United States’ National Security Agency (NSA) reveal new details outlining how Australia asked them for help to spy on Australian citizens.

An email from the acting deputy director of the Defence Signals Directorate in Canberra asks for an extension of the two agencies’ partnership to cover the increasing number of Australians involved in international extremist activities.

It specifies Australians connected with AQAP – or Al Qaeda in the Arabian Peninsula – as a target.

The document is included in a book by Glenn Greenwald, one of three journalists to whom whistleblower Edward Snowden gave a huge trove of secret intelligence documents.

Mr Greenwald says the request from Canberra detailed an increasing problem with what they called “home-grown extremism”.

“They wanted to have the NSA observe Australians more aggressively than ever before, and were making the case as to why the NSA should do that,” Mr Greenwald told ABC’s PM program.

‘Indiscriminate surveillance the problem’

Mr Greenwald says that while there is a case for legitimate state surveillance, the request from Canberra lacked specific targets.

“The problem is, and if you look at the letter … they’re not asking for very specific individuals to be surveilled. They’re asking for a wide surveillance net to be cast over the Australian communications system,” he said.

“Historically, whenever you allow government officials to engage in mass surveillance … the abuse is virtually inevitable.

“I think it would be a much different story if the letter [was] saying ‘Here are 35 people we’re concerned about and we’d like you to help us watch them’.

“But that’s not what the letter was. It was asking for, more or less, indiscriminate surveillance on Australians generally.”

When asked what he believed was the single most important thing Snowden revealed, Mr Greenwald argued that it is not about specific stories.

“Ultimately what I really believe is the most enduring and consequential revelation is that the goal of the NSA and its four English-speaking partners, which includes Australia, the UK, New Zealand and Canada, is captured by this phrase that appears over and over in the documents, which is ‘Collect it all’.”

Mr Greenwald says authorities are not simply trying to collect the communication of terror suspects or radical extremists but are instead targeting “all human beings on the planet”.

“They literally want to store and gather and … monitor and analyse all forms of human communication that take place electronically,” he said.

“If the Government is going to do something that profoundly significant, we ought to know about it and be able to debate it.”

Claims Snowden endangered lives

Mr Greenwald credits Snowden with opening that debate, but recently retired General Keith Alexander last week told the Australian Financial Review that the actions of the whistleblower endangered people’s lives. Mr Greenwald disagrees.

“I think the critical thing to note is that people who wield power in every country generally dislike transparency,” he said.

“If you look at the history of the United States over the past 50 years … in every single case where somebody has come forward and disclosed information that the government want hidden … the US government says: ‘you’re endangering lives, you have blood on your hands, you’re going to cause people to die’.

“It turns out to be completely untrue … it’s a fear-mongering technique designed to discredit basic journalism and transparency, and that’s absolutely the case here.

“There’s zero evidence that anybody has been harmed in any way by Edward Snowden’s revelations, other than the political leaders whose reputations and credibility have suffered.”

But General Alexander claims lives will be lost because authorities will not be able to protect people “with capabilities that were once effective, but are now being rendered ineffective” because of the revelations.

Mr Greenwald has labelled the claim as “absurd”, saying terrorists are already one step ahead.

“Terrorists have known forever that the US government and its allies are doing everything they can possibly do to learn the contents of their communication,” he said.

“That’s why Osama bin Laden would only communicate by human courier, because he knew that electronic means of communication were compromised.”

He insists the release of information by Snowden did not tell the terrorists anything they did not already know.

“What we told people who didn’t already know were ordinary human beings around the world, by the hundreds of millions, that the target of the surveillance system is not Osama bin Laden and his compatriots overwhelmingly,” he said.

“It is instead them, people who are guilty of absolutely no wrongdoing.”

Mr Greenwald’s book is called No Place To Hide.

Listen to the full audio of Mark Colvin’s interview on the AM website.