A related article -- I bet they found some things in those other interdictions, or they wouldn't be keeping them a secret.
Anti-WMD interdictions reach three
From correspondents in Washington
January 16, 2004
AT least three interdictions have been conducted as part of an international effort to track and intercept suspected shipments of materials related to weapons of mass destruction (WMD), a senior US defence official said today.
The best known was the interception in October of a German freighter carrying centrifuge parts to Libya, a success that some US officials believe helped persuade Libyan leader Muammar Gaddafi to renounce his country's clandestine nuclear program.
But the official said there have been at least two other interdictions under the Proliferation Security Initiative, an 11 country effort to stop the trafficking of WMD materials.
The official said he did not believe the other interdictions yielded WMD technologies, but said those operations have been shrouded in secrecy.
"PSI has conducted interdictions," said a second senior US defence official, declining to say how many there have been beyond the Libyan interception, which was publicly acknowledged by the State Department December 31.
http://www.news.com.au/common/story_page/0,4057,8405065%255E1702,00.html One of the complications behind US efforts in particular with regard to nuclear proliferation is that in many cases our ally of Pakistan (or rather, the trifecta of rogue ISI, crazy nuclear scientists, and the MMA) has been behind them in some fashion or another, at least with regard to Libya, who allegedly purchased a great deal of Pakistani nuclear technology on the open market. Iran has also exploited the Indo-Pakistani rivalry as a means to acquire nuclear technology from both sides, as well as what they receive from North Korea as part of their unofficial anti-Western alliance.
So if it's from Pakistan, the US is likely keeping it quiet in order to take some heat off Musharraf. If it came from North Korea, we're keeping quiet because either 1) we don't want Kim to know that we are intercepting his WMD shipments or 2) we don't want to stir the Korean Peninsula until we've had time enough to shift the necessary troops to the region.