In case you don’t know:

Wikileaks did publish the unredacted material after it was already in the public domain.

Let‘s have a look at the chronology:

Summer 2010:

WikiLeaks gives investigative journalist David Leigh access to the US diplomatic cables which are stored on a website as encrypted file with the filename “xyz_z.gpg”.

28 November 2010:

The Guardian, El Pais, Le Monde, Der Spiegel and the New York Times begin publishing redacted cables from WikiLeaks. WikiLeaks is subjected to a denial-of-service attack.

2 December 2010:

WikiLeaks service provider EveryDns.net terminates DNS hosting for WikiLeaks to protect its other customers against the denial-of-service attack on WikiLeaks.

4 December 2010:

Third-party organisations begin to mirror information from WikiLeaks by creating mirrors of the information on websites and BitTorrent. Some of the mirrors include the encrypted file given to David Leigh “xyz_z.gpg”.

1 February 2011:

David Leigh publishes his book WikiLeaks: Inside Julian Assange’s war on secrecy. The book disclosed the passphrase for accessing the encrypted file containing the unredacted diplomatic cables.

25 August 2011:

Der Freitag reports that it has discovered a copy of the full archive on the internet and was able to decrypt it using a passphrase found on the internet.

31 August 2011:

The website Cryptome publishes a report on the passphrase and which file it decrypts. A searchable copy of the decrypted cables appears on the website mrkva.eu. WikiLeaks makes a public statement about the disclosure of the passphrase in Leigh’s book.

1 September 2011:

A user called “droehein” creates a BitTorrent on the Pirate Bay website sharing the decrypted cables.

2 September 2011: Wikileaks republished the unredacted cables on the WikiLeaks site.

Source: Christian Grothoff, an expert in network security from the University of Applied Sciences in Bern, Switzerland