As many of you know, I'm leaving the Guardian in order to work with Pierre Omidyar, Laura Poitras, Jeremy Scahill and soon-to-be-identified others on building a new media organization. As I said when this

news was reported a couple of weeks ago, leaving the Guardian was not an easy choice, but this was a dream opportunity that was impossible to decline.

We do not yet have an exact launch date for the new outlet, but rest assured: I'm not going to disappear for months or anything like that. The new site will be up and running reasonably soon.

In the meantime, I'll continue reporting in partnership with foreign media outlets (stories on mass NSA surveillance in France began last week in Le Monde, and stories on bulk surveillance of Spanish citizens and NSA's cooperation with Spanish intelligence have appeared this week in Spain's El Mundo), as well as in partnership with US outlets. As I did yesterday when responding to NSA claims about these stories, I'll also periodically post on my personal blog – here – with an active comment section, as well as on our pre-launch temporary blog. Until launch of the new media outlet, the best way to learn of new stories, new posts, and other activity is my Twitter feed, @ggreenwald. My new email address and PGP key are here.

I'm gratified by my 14-month partnership with the Guardian and am particularly proud of what we achieved together over the last five months. Reporting the NSA story has never been easy, but it's always been invigorating and fulfilling. It's exactly why one goes into journalism and, in my view, is what journalism at its crux is about. That doesn't mean that the journalists and editors who have worked on this story have instantly agreed on every last choice we faced, but it does mean that, on the whole, I leave with high regard for the courage and integrity of the people with whom I've worked and pride in the way we've reported this story.

As I leave, I really urge everyone to take note of, and stand against, what I and others have written about for years, but which is becoming increasingly more threatening: namely, a sustained and unprecedented

attack on press freedoms and the news gathering process in the US. That same menacing climate is now manifest in the UK as well, as evidenced by the truly stunning warnings issued this week by British Prime Minister David Cameron:

British Prime Minister David Cameron said on Monday his government was likely to act to stop newspapers publishing what he called damaging leaks from former US intelligence operative Edward Snowden unless they began to behave more responsibly. "If they (newspapers) don't demonstrate some social responsibility it will be very difficult for government to stand back and not to act," Cameron told parliament, saying Britain's Guardian newspaper had "gone on" to print damaging material after initially agreeing to destroy other sensitive data.

There are extremist though influential factions in both countries which want to criminalize not only whistleblowing but the act of journalism itself (pdf). I'm not leaving because of those threats – if anything, they make me want to stay and continue to publish here – but I do believe it's urgent that everyone who believes in basic press freedoms unite against this.

Allowing journalism to be criminalized is in nobody's interest other than the states which are trying to achieve that. As Thomas Jefferson wrote in an 1804 letter to John Tyler:

Our first object should therefore be, to leave open to him all the avenues to truth. The most effectual hitherto found, is the freedom of the press. It is, therefore, the first shut up by those who fear the investigation of their actions.

I hope everyone who believes in basic press freedoms will defend those journalistic outlets when they are under attack – all of them – regardless of how much one likes or does not like them.

Finally: thanks, most of all, to my readers and commenters who participate in so many ways in the journalism I do. I've always said that my favorite aspect of online political writing is how interactive and collaborative it is with one's readers: that has always been, and always will be, crucial in so many ways to what I do.