Would you trust a politician if your liberty depended on it?

Day to day, it's something journalists in America are having to do, whether they're aware of it or not. The politician in question is Attorney General Eric Holder, and the key quote in question is his vow to Congress:

As long as I'm attorney general, [the DoJ] will not prosecute any reporter for doing his or her job.

That memo doesn't quite seem to have filtered down to federal agencies, if a recent report to Slate is to be believed. Ryan Gallagher, one of the site's security writers, has produced a long account of the strange tale of Sigurdur Thordarson, who became a WikiLeaks insider at just 17 years old, who then proceeded to voluntarily turn FBI informant.

The investigation into WikiLeaks has prompted little concern among mainstream US journalists. This might be because WikiLeaks doesn't produce the same style of journalism, or because reporters can reassure themselves, rightly or wrongly, that the investigation centers on trying to uncover any inappropriate dealings with sources, or involvement in hacking.

Such reassurances are false. What happens to WikiLeaks today happens to New York Times reporters tomorrow.

There are two reasons I can say this so starkly. The first is that we've had time to see it happen. In the last year, AP reporters learned their phone records had been secretly subpoenaed and analyzed in a bid to uncover their confidential sources. A Fox News reporter was surveilled. And veteran New York Times reporter James Risen faces jail for refusing to disclose a source.

The second reason is a little closer to home: halfway through the Slate article on the WikiLeaks mole, Thordarson gives a short list of individuals whom the FBI asked him to target, and on whom they wanted him to hand over information. Julian Assange, predictably enough, is at its head. Also present are activist and developer Jacob Applebaum, Icelandic MP Birgitta Jónsdóttir, and me.

Now, that's obviously enough of interest to me, but it has a degree of broader significance. At the time the agents were asking for the information – summer of 2011 – I was a staff reporter at the Guardian. I was also a working, mainstream journalist before – and, I would argue, during – my time at WikiLeaks: I had produced for the BBC, Channel 4, al-Jazeera, the Times, Sunday Telegraph and more. I've had professional training as a journalist.

Some reporters may split hairs over whether Assange is or isn't a journalist (my view is that he is), but it's pretty difficult to argue I'm not. The White House itself has even credentialed me as a reporter, to cover the president and the first lady, and – on one occasion – to fly with the vice-president.

I also joined WikiLeaks several months after the arrest of Bradley Manning, and before any alleged dealings by WikiLeaks with hackers in Lulzsec. That means targeting me for the purpose of ferreting out sources was unlikely. My work at WikiLeaks was that of a reporter – digging into material already obtained for stories. So what justification does that leave for pulling me into that investigation?

Of course, investigation isn't prosecution. But between an unprecedented crackdown on sources, pressure on reporters, and dragging journalists into federal investigations, the White House is skirting very close to the edge of the attorney general's promise to Congress.

For reporters, these cases should serve as a reason to keep a close watch on the WikiLeaks investigations, and others like it: what happens to alternative media may seem remote, and the outlets and their ethical standards might not meet your tastes (Assange's have certainly not always met mine), but the gulf between them and you is far narrower than it might seem.

For the Obama administration, the WikiLeaks investigation seems a needlessly self-inflicted injury, a chance for people to draw a largely false equivalence between crackdowns on journalists around the world and in the US. There is a chance to give reassurance: tell us what, precisely, is under investigation? If it's the acquisition of the material, why are people like Jónsdóttir dragged in the net? If it's the publication, why aren't the editors of the Guardian, New York Times, Spiegel, El Pais, Le Monde and others facing the same? Are investigations ongoing?

For me, for now, I'm choosing to trust Eric Holder: America is a great place to visit, to work, and to report on, and I would hate to miss out. I hope its government practices what it preaches – but being a journalist, I'd like to get confirmation.